david h. kay, u.s. dept. of 0he navy, dc...g6ran sundholm, marioff hi-fog oy (ait. to p. k....

Report of the Commit tee on

Water Mist Fire Suppression Systems

Jack IL Mawhinney, Chair Nat'l Research Council of Canada, ON

Christopher L. Vollman, Secretary RoifJensen & Assoc., Inc., TX

Rebecca Anderson,Johnson & Higgins, WA Magnus Arvidson, Swedish Nat'l. Testing & Research Inst. (SP) John F. Bender, Office of State Fire Marshal, MD

Rep. Fire Marshals Assn. of North America Robert G. Bill, Factory Mutual Research Corp., MA ~arv in n S. Casler, Fike Protection Systems, MO

Charney, Kidde-Fenwal Inc., CA Rep. Fire Suppression Systems Assn.

Salvatore A. Chines, Industrial Risk Insurers, CT Robert L. Darwin, U.S Dept. of the Navy, DC Jack W. Davis, Sprinkler Fitters Local 483JAC, CA

Rep. United Assn. of Journeymen/Apprentices of Plumbing/Pipe Fitting John F. Devlin, Schirrner Engr, Corp., VA Philip J. DiNenno, Hughes Assoc., Inc., MD William A. Eckholm, Hochiki America, CA William J. Fries, Liberty Mutual Insurance Cos., MA

Rep. The Alliance of American Insurers William A. Froh, U.S. Dept. of Energy, DC Victor Gameiro, Securiplex Technologies Inc., P Q John A. Gioseffi, Bro~ard Fire Equip & Serv Inc., FL

Rep. Nat'l Assn. of Fire Equipment Distributors Inc Matthew T. Gustafson, U.S. Coast Guard, DC Raymond N. Hansen, U.S. Air Force, Civil Engr Support Agency, FL Thomas W. Jaeger, Gage Babcock & Assoc., Inc., VA George E. Laverick, Underwriters Laboratories Inc., IL Paul IL Marttila, Marioff Hi-fog Oy, PA M. L. "Larry ~ Maruskin, U.S. Fire Administration, MD Kathy A. Notarianni, U.S. Nat'l Inst. of Standards and Technology, MD Jerome S. Pepi, Grinnell Corp., RI

Rep. Nat'l Fire Sprinlder Assn. Lyle IL "Skip" Perkins, Florida Power Corp., FT,

Rep. Electric Light Power Group/Edison Electric Inst. hn F. Scarff, Marriott Corp., DC chael B. Stevens, NASA Kennedy Space Center, FL

Thomas F. Ziegler, GTE Service Corp., CT

Alternates

james G. Bisker, U.S. Dept. of Energy, DC (/kit. to W. A. Froh)

William M. Carey, Underwriters Laboratories Inc., IL (Alt. to G. E. Laverick)

Paul H. Dobson, Factory Mutual Research Corp., MA (Alt. to 1L G. Bill)

Russell P. Fleming, Nat'l Fire Sprinkler Assn., NY (Alt. toJ. s. Pepi)

ThomasJ. Forsythe, Gage-Babcock & Assoc., CA (Alt. to T. W.Jaeger)

Pierre Girard, Securiplex Technologies Inc., 'PQ (Alt. to V. Gameiro)

Morgan J. Hurley, U.S. Co~st Guard, DC (Alt. to M. T. Gustafson)

David H. Kay, U.S. Dept. of 0he Navy, DC (Ait. to 1L L. Darwin)

George A. Krabbe, Automatic Suppression Systems Inc., IL (/kit. to M. Charney)

Jane I. Lataille, Industrial Risk Insurers, CT (Alt. to S. A. Chines)

Daniel Madrzykowski, U~S. Nat'l Inst. of Standards & Technology, MD (Alt. to K. A. Notarianni)

Norbert W. Makowka, Nat'l Assn. of Fire Equipment Distributors (NAFED), IL

(Alt. toJ. A. Gioseffi) Joseph V. McEivaney, Schirmer Engr, Corp., TX

(Alt. toJ. F. Devlin) Earl D. Neargarth, bike Protection Systems, MO

(Alt. toJ. s. Casler) Erin A. M. Oneisom, U.S. Air Force, Civil Eng. Support Agency, FL

(Alt. to 17,- N. Hansen) Martin H. Reiss, RolfJensen & Assoc., Inc., MA

(Alt. to C. L. Vollman) Anders Ryderman, Swedish Nat'l Testing & Research Inst.

(Ait. to M. Arvidson) John A. Sileo,Johnson & Higgins, CT

(Alt. to R. Anderson) G6ran Sundholm, Marioff Hi-fog Oy

(Ait. to P. K. Marttila) Phillip Tapper, NASA, DC

(Alt. to M. B. Stevens)

Nonvoting

James IL Butz, ADA Technologies, Inc., CO Stephen G. Leeds, Lawrence Livermore Nat'l. Laboratory, CA

Rep. T /C on Electronic Computer Systems DouglasJ. Pickersgill, Fire and Safety Systems, QU Antony Turner, Technisch Bureau Steur GMBH Fernando Vhgara, Vimpex - Security Devices, SA

Staff Liaison: Robert E. Solomon

This list represents the membership at the time the Committee was balloted on the text of this edition. Since that time, changes in the membership may have occurred.

Committee Scope: This Committee shall have primary responsibility for documents on the design, installation and maintenance of systems which use a water mist for the control, suppression or extinguishment of fire.

The Report of the Technical Committee on Water Mist Fire Suppression Systems is presented for adoption.

This Report was prepared by the Technical Commit tee on Water Mist Fire Suppression Systems and proposes for adoption a new document NFPA 750-1996, Standard for the Installation o f Water Mist Fwe Protection Systems.

This Report has been submited to letter ballot of the Technical Commit tee on Water Mist FLre Suppression Systems, which consists of 30 voting members. The results of the balloting can be found in the report.

649

N F P A 7 5 0 - - A 9 6 R O P

(Log #4) 750- 1 - (Title): Accept SUBMITTER: J o h n J . Walsh, Uni ted Association RECOMMENDATION: Change "suppression" to "protection". SUBSTANTIATION: The proposed s tandard addresses control as well as ext inguishment . With the s tandard governing systems des igned for control, the title is inappropr ia te and needs to be changed. COMMITTEE ACTION: AccepL NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 29 ABSTENTION: 1

EXPLANATION OF ABSTENTION: GIOSEFFI: Since I am a newly appoin ted m e m b e r to the Water

Mist Commit tee and have not been involved in the deliberat ions up to this po in t - I have elected to abstain on the ROP b,'dlot.

(Log #60) 750- 2 - (Chapter 1 Revised): Reject SUBMITTER: Erik Pedersen, Danish Fire Research & Development Group RECOMMENDATION: DEF, page 8; Water Mist System

..., is less than 400 microns. DEF, new; Water Spray System: 400 - 1000 microns.

SUBSTANTIATION: 1) The efficiency depends on drople t size as on parameter . The h igh value prepared will lead to cheaper and less efficient systems.

2) Technology is already available. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: See the Commit tee Action on 750-3 (Log #61) and 750-7 (Log #96). In addition, see the Appendix text for A-l-4.1. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: DINENNO: The cur ren t definit ion of water mist and the classes of

water mist are arbitrary and without foundat ion. However, there are no immedia te practical problems caused by dlese arbitrary definitions.

GIOSEFFI: See my Explanat ion of Abstent ion on 750-1 (Log #4).

(Log #61) 750-3- (1-4.1): Reject SUBMITTER: J e r o m e s. Pepi, Grinnell Corp RECOMMENDATION: Replace existing text with:

"Water mist consists of a spray which utilizes droplets of a size less than 400 microns to extinguish, suppress or control fires." SUBSTANTIATION: The wording of the existing test unnecessari ly restricts the deve lopment of new water mist techffology and, specifically technology that utilizes droplets up to a n d g r e a t e r than 1000 microns to help carry fine droplets (less than 400 microns) a long to the immedmt e area of a fire. COMMITI'EE ACTION: Reject. COMMITTEE STATEMENT: T he Technical Commit tee has focused on the deve lopment and re f inement of this~definition since the first mee t ing in October of 1993. While it is recognized that the technology may be changing, and is to some extent a moving target, the Commit tee believes t h a f t h e cur rent definit ion allows fo~a bioad range of mist ing technology devices. There is no overwhelming evidence that the cur ren t defini t ion in any way restricts or precludes water mist technology. Systems t h a t p r o d u c e larger droplets (greater than 1,000 micron) resemble water spray device ctlaracteristics and may properly belong in NFPA 15, Water Spray Fixed Systems. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: DINENNO: See my Explanat ion of Abstent ion on 750-2 (Log #60). GIOSEFFI: See my Explanation of Abstention on 750-1 (Log #4).

(Log #65) 750- 4 - (1-4.1): Accept in Principle SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: The "substantially all..." included in the definit ion of low, in termedia te and higla pressure systems definit ion should be clarified. This expression s~ould be replaced by a clear listing of the componen t s o i n o t be so vague leaxa'ng a large place for interpretation.

SUBSTANTIATION: Securiplex' equipment , as part of the water mist system (air cylinders, discharge hose, manifold, check valve, regulator) are rated at 2400 psi or higher, while the other parts have an ope ra t ingpressu re of 85-90 psi. COMMITTEEACTION: Accept in Principle.

Revise the definit ion for High Pressure System to read: A water mist system where the distribution system is exposed to

pressures of 500 psi (34.5 bars) or greater." COMMITTEE STATEMENT: It is in tended that the pressure categories be based upon the pressures at which the piping and nozzles are subject to either the normal condit ion or the discharge condition, whichever situation results in the h igher pressure. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE O N COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: GIOSEFFI: See my Explanation of Abstention on 750-1 (Log #4).

(Log #97) 750- 5 - (1-4.1 DV 0.99, DV 0.90 (New)): Accept in Principle SUBMITTER: J. R. Mawhinney, National Research Council of Canada RECOMMENDATION: Editorial revision to existing definition:

DV0.99 - drop diameter such that 99 percent of the total liquid volume is in drops of smaller diameter.

DV0.99 was def ined in the draft as "a drop size distribution of a liquid spray..." In fact it is a representative diameter that pardy characterizes the drop size distribution, it is no t itseff a drop size distribution. The proposed revision is editorial. The wording is taken f rom ASTM E 799.

Add new definition: DV0.90 - drop diameter such that 90 percent of the total liquid

volume is in drops of smaller diameter. SUBSTANTIATION: The definitions of Water Mist, Class 1 mist, and Class 2 mist, use the characteristic d iameters DV0.99 and DV0.90, as def ined by ASTM E-799-92. DV0.99 was def ined in the draft. With the addit ion of definit ions for classifying mists as Class 1, 2, or 3, based on the DV0.90, it is necessary to define tha t te rm as well.

Note: Instructions to the listing authorit ies mus t be provided to describe the m e t h o d for obta ining representative values of DV0.99 and DV0.90. One approach would be to use the Appendix to describe a method , such as proposed by the drop size m e a s u r e m e n t me thods Task Group. C O M M I T r E E A C T I O N : Accept in Principle.

Provide a general defini t ion and descript ion for drop m e a s u r e m e n t parameters as follows:

"Dvf- A d rop d iameter such that the cumulative volume, f rom zero diameter to this respective diameter, is the fraction (f) of the cor responding sum of the total distribution.

Note: Dv 0.50 is the volume median diameter; tha t is, 50 percent of the total volume of liquid is in drops of smaller d iameter and 50 percent is in drops of larger diameter." COMMITTEE STATEMENT: This definit ion provides a generic description of this term. This allows the user or the manufac tu re r to utilize a base value and f ind the cumulative drop distribution at any

int. This descript ion is taken f rom ASTM E 1296, Page 13. ER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30

VOTE ON COMMITTEE ACTION: AFFIRMATIVE: 29 ABSTENTION: 1


(Log #62) 750- 6 - (1-4.1 Water Mist): Reject SUBMITTER: L.R. "Skip" Perkins, Florida Power Corp. RECOMMENDATION: Water Mist. A water spray for which the DVO.99 as measu red at the coarsest part of the spray in a plane 1-m f rom the nozzle, at its m i n i m u m design operat ing pressure, is less than 400 microns. SUBSTANTIATION: Generally, all informat ion to date on water mist relates to water drople t sizes that are u n d e r 400 microns. The NFPA 750 Commit tee needs to confine the writing of this Water Mist S tandard for systems which mee t this criteria and refer larger water drople t sized systems to NFPA 15 as a second genera t ion water fine

ray system. MMITI 'EE ACTION: Reject.

COMMITTEE STATEMENT: See the Commit tee Action on 750-7 (Log #96). Also see new Appendix i tem for A-l-4.1.

650

N F P A 750 ~ A96 R O P

NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: DINENNO: See my Explanat ion of Abstention on 750-2 (Log #60). GIOSEFFI: See my Explanation of Abstent ion on 750-1 (Log #4).

(Log #96) 750- 7 - (1-4.1 Water Mist (New)): Accept in Principle SUBMITTER: J. R. Mawhinney, National Research Council of Canada RECOMMENDATION: Add three new definitions, as follows:

Class 1 Mist: Is a water mist for which 90 percent of the volume of the spray conta ined in drops with diameters less than 200 microns (DV0.90<200).

Class 2 Mist: Is a water mist dlat is no t a Class I mist, for which 90 percent of the volume of the spray is conta ined in drops with diameters less than 400 microns (DV0.90<400).

Class 3 Mist: Is a water mist dlat is no t a Class 1 or a Class 2 mist. SUBSTANTIATION: There are two reasons to subdivide water mist into three classes. The first has to do with safe and effective use of water sprays on different types of combustibles. The second has to do with the potential ff~r o ther regulat ions (EPA or OSHA) to be applied to water mists in general, when only the f iner mists are the in t ended targets.

The definit ion of "water mist" in the first draft of NFPA 750 includes all water sprays for which 99 percent of the volume of the spray is conta ined in drops with diameters less than 1000 microns (DV0.99<1000). Tha t definit ion encompasses too broad a range of water sprays to be useful for engineer ing water mi~t systems for the expected range of applications. It includes all water sprays used in NFPA 15 Water Spray Systems, sprays p roduced by s tandard sprinklers operat ing at high pressure, as well as light mists suitable for g reenhouse mist ing and HVAC humidif icat ion systems. Research indicates that drops with diameters greater than approximately 400 microns can agitate the surface of liquid filel fires and intensify burning . Where water mists systems are used to minimize wetting ofv;duable commodit ies , it is undesirable to have a significant fraction of spray in droplets larger than 400 or 500 microns. O n the other band, veryf ine mists (such as those with DV0.90<200 microns) may not be suitable for use on ordinary combustibles, due to dleir inability to achieve fuel wetting, which can be impor tan t for ex t ingu i shment of Class A combustibles. A single definit ion of water mist, encompass ing the coarse as well as the fine sprays, gives the false impression that any spray that meets the definit ion of "water mist" is suitable for any proposed application. B y i n t r o d n c i n g a v o c a b u l a r y t o allow designers to dist inguish between the spray characteristics, the relationship betweela spray characteristics and application will be much clearer.

The Environmental Protection Agency (EPA), and OSHA, have expressed concern about the potential to spread disease organisms if water supplies become contaminated. They may int roduce federal regulat ions to require special water storage a r rangements for "water mist" fire suppress ion systems to reduce the risk of bacterial contaminat ion of the s tored water. Such measures will increase the cost of water mist systems, as well as the engineer ing difficulties to be overcome in the design. The concern is that dae very fine fraction of water mist could be a t ransport vector for bacterial agents such as legionella. By in t roducing a vocabulary to subdivide water mist into fine and coarse classifications, it may be possible to limit application of those regulat ions to only those that pose a potential problem, viz,, Class 1 mists. COMMITI'EEACTION: Accept in Principle.

Accept the classifications as suggested and place them as a subset to 1-4.1, ' 'Water Mist" definition. Take the substantiat ion and include it in the Appendix as part of A-i-4.1 with the exception of the last sentence.

A-l-4.1 The division of"water mist" into three classes permits description of the sprays in more precise terms than "finer" or "coarser". The definit ion of "water mist" in this s tandard includes all water sprays for which 99 percen t of the volume of the spray is conta ined in drops with diameters less than 1000 microns (Dv0.99<1000). This definit ion is so broad that some impor tan t differences in the qualities of sprays are disguised. It includes, for example, all water sprays used in NFPA 15 Water Spray Systems, sprays p roduced by stat~ldard sprinklers operat ing at high pressure, as well as light mists suitable for g r eenhouse mist ing and HVAC humidif icat ion systems. Each of these sprays may or may not be suitable for certain applications for water mist fire suppress ion systems.

The relationship between drop size distr ibution and ext inguishing capacity of a water mist is complex. In general , Class I and Class II

651

sprays are successful at ext inguishing liquid fuel fires without agitation of liquid pool surfaces. Class III sprays have been used successfully on pool fires, however. Also in general, it is difficult to ext inguish Glass A combustibles with Class I mists, which may no t achieve the fuel wetting necessary to penetra te the char layer. Class A fires have been ext inguished with Class I mists, however. This evidence indicates that drop size distr ibution is no t the only spray characteristic that de te rmines the ability of a spray to ext inguish a given fire. Factors such as enclosure effects, spray flux density an d spray m o m e n t u m combine to create condit ions that lead to ext inguishment .

By in t roducing a vocabulary to allow designers to dist inguish between "coarser": and "finer" sprays, the relationship between drop size distribution, flux density, m o m e n t u m and enclosure effects wi l l be better unders tood. COMMITTEE STATEMENT: A fur ther classification and explanat ion of water mist sizes is useful. By describing the complex relationship between drop size, flux density, spray m o m e n t u m an d enclosure of facts, the user should have a better unde r s t and ing of the behavior of various water mist drop size distributions. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 28 NEGATIVE: 1 ABSTENTION: 1

EXPLANATION OF NEGATIVE: DINENNO: The classification system as proposed is premature ,

and the categories are arbitrary and without widespread ag reem en t in the water mist research community . There are two reasons given for the need for such classification.

O n e relates to a potential need for such classification by regulatory aufllorifies. Current proposed regulat ions by the EPA do not refer to this classification or make any reference to a particular acceptable or unacceptable droplet size range related to the proposed classification.

As for the need for classification for purposes of design, it is m u c h too early in the deve lopment of this technology to provide design guidance based on the proposed classification. Some of the more general guidance related to drop size may be true in some cases, but it is no tposs ib le to derive any rules or generalized guidance. The s tandardrecognizes this fact t h r o u g h o u t in requir ing specific application testing and approval.

The p remature promulga t ion of an arbitrary classification system may cause substantial p roblems in the future as a f i rmer technical base evolves. An example may be for droplets below 50 ~tm having substantially different characteristics than cur rent "Class I" sprays.

Classification of sprays mad their characteristics without regard for o ther factors such as droplet concentrat ion, spray m o m e n t u m , spray pat tern characteristics, etc., is misleading. Any potential general ized design rules mus t consider these and many other variable. The per formance of systems in the same class varies widely between manufac ture rs and technologies. Since we are unable to provide valid generalizable guidance for designers based on this classification scheme and such a classification is arbitrary and may be misleading, I am voting negatively. I would have no objection to moving the discussion to the Appendix with more 9aut]onary wording regard ingi t s limitations. EXPLANATION OF ABSTENTION:

GIOSEFFI: See my Explanation of Abstention on 750-1 (Log #4).

(Log #64) 750- 8 - (1-4.1 Water Mist System): Reject SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: The "Water Mist System" definition should clearly identified that a distr ibution system is no t only connec ted to a water supply:., but also to air. The sentence should read: "A distribution system connec ted to a water and atomizing media supplies..." SUBSTANTIATION: The definit ion of water mist system, as written, does no t include the twin fluid technology. COMMITrEE ACTION: Reject. COMMITTEE STATEMENT: The cur rent definit ion does not preclude the use of air in p roduc ing the appropriate d rop sizes to genera te the mist. The system will always have a water supply and various me thods of p roduc ing the mist are considered acceptable. Those include imp ingemen t me thods as well as air atomization methods. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



N F P A 750 - - A 9 6 R O P

(Log #20) 750- 9 - (Table 1-4.2.2): Reject SUBMITTER: Jack Davis, Sprinkler Fitters U.A. Local 483Join t pAj~Pcrenticeship Commit tee

OMMENDATION: Ten th line change to read bar - bar - 1 bar = 14.5 psi. SUBSTANTIATION: Readers not thoroughly familiar with the metr ic system have a need to relate the whole uni t bar to the un i t

psi. ec COMMITTEE ACTION: Rej t. COMMITTEE STATEMENT: The Technical Commit tee does not see a benefi t to dais extra conversion. A conversion factor for PSI to BAR is currently shown. Other conversions can be readily made from this information. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: GIOSEFFI: See my Explanat ion of Abstent ion on 750-1 (Log #4).

(Log #19) 750- 10 - (Table 1-4.2.2 (New)): Accept in Principle SUBMITTER: Jack Davis, Sprinkler Fitters U.A. Local 483Join t

rent iceship Commi t tee OMMENDATION: Add uni t m e a s u r e m e n t of micron (Micron

~t or m u 25,400 microns = 1 in.) SUBSTANTIATION: T he micron is one of the basic units of m e a s u r e m e n t used in this s tandard. Readers no t thoroughly familiar with the metr ic system have a need to relate the un i t micron to the un i t inch. C O M M I T r E E A C T I O N : Accept in Principle.

Provide an addit ional conversion value as follows: 1 m m = 1,000 ~t (1,000 microns)

COMMITTEE STATEMENT: The Technical Commit tee has elected to provide a conversion between m m and microns. Additional conversions to o ther English units can be made f rom dais

ER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: GIOSEFFI: See my Explanat ion of Abstention on 750-1 (Log #4).

(Log#21) 750-11 - (1-8 (New)): Reject SUBMITTER: Jack Davis, Sprinkler Fitters U.A. Local 483Jo in t Apprent icesh ip Commit tee RECOMMENDATION: Add a new 1-8 to read: Installation work shall be done by fully exper ienced and responsible persons. SUBSTANTIATION: T he potential for the back yard mechan ic is too great. Other NFPA standards recognize the need to insure that the work pe r fo rmed on complicated fire protect ion systems is done by people tha t are reliable and experienced. T he addit ion o f this paragraph will give the authori ty having jur isdict ion some help in combat in shoddy workmanshi COMMII~I!EE ACTION: RejecP: COMMITTEE STATEMENT: T he Technical Commit tee believes that the authori ty having jurisdict ion is in the best position to control the qualifications of the installer. E a c h j u n s d i c d o n mus t establish the level of experience, qualification and responsibility necessary to install these systems. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: GIOSEFFI: See m y Explanation of Abstent ion on 750-1 (Log #4).

(Log #66) 750- 12- (2-1.2): Reject SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: T he m i n i m u m working pressure of no t less than 175 psi shou ld be changed to no t less than 150 psi. SUBSTANTIATION: Securiplex water mist system has some componen t s rated less than the p roposed 175 psi. Several componen t s inc luding our flow control valve and low pressure solenoid valves' pressure range is 0 - 150 psi, which is below the stated 175 psi.

C O M M I T r E E ACTION: Reject. C O M M I T r E E STATEMENT: NFPA 750 has correlated with other NFPA standards. 175 psi is a c o m m o n threshold value which is applicable to many o ther system piping materials. The range of values given are operational but would no t preclude the device f rom being exposed to a rated pressure of 175 psi. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF NEGATIVE: CHARNEY: The 175 psi m i n i m u m value is arbitrary an d only

applies to low pressure systems by definition. If this logic was followed, t hen all Intermediate Pressure System components , by definition, should be rated at no t less than 500 psi, and so on. However, no such similar requ i rements have been applied to in termediate or high pressure systems.

ff a low pressure water mist system is des igned for pressures less than 175 psi t hen the system componen t s should be rated for the m a x i m u m anticipated work ingpressure for that system.

I r e c o m m e n d that paragraph 2-1.2 be revised as follows so that it is applicable to all type systems, without impos ing special requi rements on any one type of system.

Revise paragraph 2-1.2 to read: "System componen t s shall be rated for the m a x i m u m working pressure for which they are listed."

DINENNO: There is no reason to require an arbitrary 175 psi th reshold if a c o m p o n e n t is exposed to substantially less pressure in the system design. The r equ i r emen t shou ld be based on the actual working pressure. EXPLANATION OF ABSTENTION:

GIOSEFFI: See my Explanation of Abstent ion on 750-1 (Log #4).

(Log #22) 750- 13- (2-2.2.1 (New)): Reject SUBMITTER: Jack Davis, Sprinkler Fitters U.A. Local 483Join t A ~ r e n t i c e s h i p Commit tee

OMMENDATION: Add after installation: " including seismic restraint when required." SUBSTANTIATION: Containers o f this type will require Seismic protect ion when installed in ear thquake p rone areas. Tanks of this na ture probably will be const ructed of corrosion resistance materials or epoxy lined. The restraint should be incorpora ted in the design to accommoda te the welding of a t t achmen t points and or gussets. Field welding of tanks or containers without the manufac ture rs

OSMMiTrrOVal should be prohibited. EE ACTION: Reject.

COMMITTEE STATEMENT: Section A-2-2.2.1 indicates that special e q u i p m e n t features for seismic areas shou ld be considered. All systems do no t necessarily have to be provided with any special features for use in seismic areas, thus it is no t necessary to include this criteria in all cases. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #59) 750- 14- (2-2.2.3, 2-2.2.4, 2-8.4, 2-8.5, 2-10.3.2, 3-3.5.8, +3.3.2, 4-3.3.3, A-5.2.3, 7-2.1 Exception and 7-6.2.2): Reject SUBMITTER: Matthew M. Bebich, Phirex Australia RECOMMENDATION: We wish to formally lodge our response to the above NFPA Proposed Draft concern ing the Standard for the Installation of Water Mist Fire Suppress ion Systems. We unders tand tha t the above Standard is still in its infant stage and is only a "draft report" as such. Phirex Australia supply and install the Mistex- Atomized Water Mist Fire Suppress ion System on board mar ine vessels and f ixed land installations. Therefore , our inpu t an d r ecommenda t ions are as follows:

2-2.2.3 To be a m e n d e d to read as follows: "Each water container shall have a p e r m a n e n t namepla te or other

p e r m a n e n t marking afftxed to the cylinder or indelibly stenciled on the cylinder specifying the manufac tu res name of the cylinder; date of manufacture ; cylinder capacity;, cylinder serial number ; n a m e of the particular system; pa ten t n u m b e r of the system; date of last service; the liquid contained there in ( including additives); nomina l water volume; and pressure of cylinder (where applicable)".

2-2.2.4 To be a m e n d e d to read as follows:

652

N F P A 750 - - A 9 6 R O P

"External s ight glasses on water containers shall be protected against mechanical damage a n d / o r thermal shock".

2-8.4 To be a m e n d e d to read as follows: "Individual strainers or filters for water mist nozzles shall be

required and strainers or filters mus t be listed individually to form and be part of a water mist nozzle".

2-8.5 To be a m e n d e d accordingly:. "Strainers and filters shall be required for each water mist nozzle

and mus t be sized and be a type in accordance with the listed nozzle manufac tu re r specifications".

2-10.3.2 To be a m e n d e d to read as follows: "Operat ion shall be listed mechanical , electrical, p n e u m a t i c or

fusible link means. An adequate and reliable auxiliary source of energy (e.g., approved listed battery) shall be used for electric actuat ion systems".

3-3.5.8 To be a m e n d e d to read as follows: "Inert Gas. Where h igh pressure inert gas cylinders are used, the

inert gas shall be in t roduced th rough a pressure regulator set to mainta in system pressure in accordance with 3-3.5.7. High pressure cylinders shall have fitted a listed pressure relief valve set to operate at one h u n d r e d and twenty five percent (125%) of the rated storage pressure for the inert gas cylinder".

4-3.3.2 To be a m e n d e d to read as follows: "Distance f rom Walls. The distance f rom nozzles to walls shall no t

exceed one-half of tile allowable distance between nozzles. Unless there are water mist nozzles f rom ano the r branch above or below".

4-3.3.3 To be a m e n d e d as follows: "Obstruct ions to Nozzle Discharge: The location of nozzles with

respect to obstructions shall be in accordance with the listing. The percentage of the obsuaaction should facilitate that percentage of extra nozzles required to ensure effective operat ion of the system".

4-5.2.3 To be a m e n d e d to read as follows: "Discharge t ime delays shall no t be used as a means of conf i rming

operat ion-of a detect ion device before automat ic actuat ion occurs. The system shall be des igned to automatically actuate within one (1) minu te f rom the t ime o f detect ion a n d / o r sound ing of warning audible alarm".

7-2.1 To be a m e n d e d to read as follows: "Pressure source componen t s shall be located as close as possible to

the hazard or hazards they protect, bu t should be located outside of the protected area".

"Exception: Wbere circumstances require componen t s to be in the hazard area, then an enclosure shall be appropriate to the hazard and acceptable to the Authori ty Having Jurisdict ion ' .

7-6.2.2 To be a m e n d e d to read as follows: "Pumps supplying water mist systems as the primary source shall be

automaticalb,/-controlled and shall be of sufficient capacity to mee t the system demand" . SUBSTANTIATION: The above revisions are r e c o m m e n d e d as suggested. Hoping you find the above changes suitable, and should you have any fur ther queries, please contact the writer direct. We shall await your revamped version as soon as it becomes available, and we would like to assist fur ther should this be required. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: T he proposed version of NFPA 750 covers these topics globally. This proposal is manufac tu re r specific and for the most part, sbould not be required for all system types in all cases. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: GIOSEFFI: See my Explanation of Abstention on 750-1 (Log#4) .

(Log #6) 750- 15 - (2-3): Reject SUBMITTER: J o b u J . Walsb, Uni ted Association RECOMMENDATION: Relocate second sentence of 2-3.3.4 as first sentence of 2-3.5. SUBSTANTIATION: 2-3.2 specifically allows bending for low pressure systems. 2-3.3 covering h igher pressure systems is silent. 2-3.5 apparent ly addresses all types of systems, ff the in tent is to

address all types, the above proposal should be accepted, ff the in tent is to permi t bending for low pressure systems only. 2-3.5 as a m e n d e d by this proposal should become a new 2-3.2.4. C O M M I T r E E ACTION: Reject. COMMITTEE STATEMENT: Low pressure pipe systems (See 2-3.2.3) should mainta in their own set of criteria for bending . Section 2-3.5 is i n t ended to provide guidance for copper tub ing only. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #67) 750- 16 - (2-3.1): Accept in Principle SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: The corrosion resistance of the t u b i n g / piping used should be identified to an ASTM s tandard or equivalent only and should no t be compared to ano the r material like copper. SUBSTANTIATION: Compar ing the t ub ing /p ip ing to copper may be strict as some Authori ty Having Jurisdict ion will accept black pipe for some installations. Securiplex wants to r e c o m m e n d the use of dgalwanized steel pipe a n d fittings for their installation. The

efinition is no t clear on whe the r or no t it is permit ted. COMMITI'EE ACTION: Accept in Principle. COMMITTEE STATEMENT: The referenced materials in Table 2-3.1 include comparable materials to be used as a baseline for establishing corrosion resistance levels. Paragraph 2-3.1 requires compar ison of materials in the table when de te rmin ing the corrosion resistance equivalency. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: GIOSEFFI: See my Explanation of Abstent ion on 750-I (Log #4).

(Log #68) 750-17 - (2-3.2.2): Reject SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: This article shou ld say: "The wall thickness of the t u b i n g / p i p i n g used in a water mist system shou ld be suitable for the expected working pressure of the system." SUBSTANTIATION: Securiplex does no t use K, L, or M type copper. Other types of copper tub ing will be used. Therefore, specifying the wall thickness as a funct ion of operat ing pressure migh t be more suitable. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The s tandard as written does no t prohibi t types of copper o ther t han K, L, and M. Other types of copper tube which have wall thickness comparable to type K, L, or M are acceptable. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMrrTEE ACTION:



(Log #7) 750- 18- (2-3.3.2): Accept in Principle SUBMITI'ERa J o h n J . Walsh, Uni ted Association RECOMMENDATION: Modify to read:

"...shall be listed and have pressure ratings compatible with the listing of the systems." SUBSTANTIATION: Paragraph A-2-4.2.3 recognizes the need for listing. The s t ronger wording should be in the body of the standard. COMMITTEE ACTION: Accept in Principle. COMMITTEE STATEMENT: A revision to the text of 2-3.3.2 requires these componen t s to be listed for their i n t ended use. This should satisfy the in tent of the submitter. NUMBER OF COMMITrEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #23) 750- 19- (2-4.1.1 (New)): Reject SUBMITTER: Jack Davis, Sprinkler Fitters U.A. Local 483Join t Apprent iceship Commit tee RECOMMENDATION: Joints shall be assembled by persons familiar with the particular materials being used and in accordance with the manufac tu res installation and specifications. SUBSTANTIATION: Pressures in some water mist systems may reach 400 psi. The type of fittings used in water mist systems may wary f rom plastic to stainless steel. The connec t ing processes may be glued, flared, compressed, screwed, brazed, soldered, or welded.

653

N F P A 7 5 0 m A 9 6 R O P

The anthori ty having jur isdict ion needs this wording to provide minimal workmanslf ip standards. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: This provision may be relevant for considerat ion in Chapter 4. It is an installation item, ra ther than a c o m p o n e n t issue. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #69) 750- 20 - (2-4.2.1): Accept in Principle SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: The use of stainless steel fittings shou ld no t be restricted to the DIN 235 standards. SUBSTANTIATION: The ANSI/ASME B36.19M standard is j u s t as suitable for the stainless steel fittings. COMMITTEE ACTION: Accept in Principle. COMMITTEE STATEMENT: See the cur ren t version of Table 2- 4.2.1. Three separate ASTM standards are now included and which will b roaden the range of stainless steel fitting options. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE O N COMMITTEE ACTION:



(Log #24) 750- 21 - (2-5.5 (New)): Accept in Principle SUBMITTER: Jack Davis, Sprinkler Fitters U.A. Local 483Join t

renticeship Commit tee OMMENDATION: Add text as indicated by the following:

2-5.5 Powder-Driven Stnds and Welding Studs. 2-4.4.1" Power driven studs, welding studs, and the tools used for

installing these devices shall be listed. Pipe size, installation position, and construct ion material into which they are installed shall be in accordance with individual listings.

2-5.5.2 Representative samples of concrete into which studs are to be driven shall be tested to de te rmine tha t the studs will hold a m i n i m u m load of 750 lb (341 kg) for 2-in. (51-mm) or small pipe, 1000 lb (454 kg) for 2 1 / % 3-, or 3 1/2-in. (64-, 76-, or 89-mm) pipe, and 1200 lb (545 kg) for 4- or 5-in. (102- or 127-mm) pipe.

2-5.5.3 Increaser couplings shall be a t tached directly to the powder-driven studs or welding studs.

2-5.5.4 Welding studs or o ther hange r parts shall no t be a t tached by welding to steel less than U.S. Standard, 12 gauge.

A-2-5.5.1 Powder-driven studs shou ld not be u s e d i n steel of less than 3 1/16 in (4.8 mm) total thickness.

A-2-5.5.2 The ability of concrete to hold the studs varies widely according to type of aggregate, quality of concrete, and proper installation. SUBSTANTIATION: The use of power-driven studs and welding studs for water mist systems will require at least the same restrictions as the t ime tested sprinkler systems requirements . COMMITTEE ACTION: Accept in Principle.

Revise p roposed 2-5.5 as follows: 2-5.5 Powder driven fasteners shall no t be used to attach hangers

to the bui lding structure where systems are required to be protected against ear thquake.

Exception: Powder driven fasteners shall be permi t ted where they are specLfically listed for service in seismic areas. COMMITTEE STATEMENT: The Technical Commit tee believes tha t this is the only criteria which should be placed in the proposed section. Paragraph 2-5.1 already requires these types of devices to be listed. Additional detail beyond these i tems is no t required. NUMBER OF COMMITTEE MEMBERS E L I G I B L E T O VOTE: 30 VOTE ON COMMITTEE ACTION:



654

(Log #70) 750- 22 - (2-6.1): Reject SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: We r e c o m m e n d that the DV0.99 only be given. SUBSTANTIATION: The drop size distribution is confidential information and should no t be inc luded in any listings. Distribution of such informat ion could lead to a misinterpretat ion for a designer who does no t know the exact behavior of the water mist system h e / she is proposing. The design manua l will state what type of fire the system is des igned to ext inguish rend ing the drop size distribution irrelevant. CO MMITrEE ACTION: Reject. COMMITTEE STATEMENT: See revised text for A-2-6.1. This appendix section provides a n u m b e r of e lements which should be considered but does no t stipulate what distr ibution curve, if any, should be made public as a par t of the manufac ture rs information. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VO TE ON COMMITTEE ACTION:



(Log #8) 750- 23 - (2-7.1): Accept in Principle SUBMITTER: J o h n J . Walsh, Uni ted Association RECOMMENDATION: Modify to read:

"All valves in supply piping to nozzles shall be listed indicating valves." SUBSTANTIATION: It may be all r ight for drain and test valves to only be approved and no t be of an indicating type but valves control l ing the flow to nozzles require listing and visual indication of

osition. OMMITI'EE ACTION: Accept in Principle.

COMMITrEE STATEMENT: The revised text for 2-7.1 does require critical valves to be listed. An exception waives the listing for i tems such as dra in valves and test valves. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: GIOSEFFI: See my Explanation of Abstent ion on 750-1 (Log #4).

(Log #42) 750- 24 - (2-9.2): Accept in Principle SUBMITTER: Paul H. Dobson, Factory Mutual Research Corp. RECOMMENDATION: Other types of p u m p s used in water mist systems shall be listed and installed in accordance with the p u m p manufac tu re r ' s r ecommenda t ions . . . . . ,vlz ..~d ~, d .~ , ~.tu; . . . . . . . . t~ .~f

SUBSTANTIATION: Where a p u m p is needed for satisfactory operat ion of the system it should be listed, ff installation of the p u m p is not covered unde r NFPA 20 would expect that the listing agency would check the manufac tu re r ' s installation recommenda t ions . COMMITI'EE ACTION: Accept in Principle. CO MMITrEE STATEMENT: A complete revision to Section 2-9 has been accepted by the Committee. A change to paragraph 2-1.1 requires essential equ ipmen t to be listed. This provision would ex tend to the pump. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #1 ) 750- 25 - (2-9.4): Accept in Principle SUBMITTER: J o h n J . Walsh, Uni ted Association RECOMMENDATION: Change of "approved types" to "listed". SUBSTANTIATION: Proposed wording is too weak. NFPA 20 requires listing and to avoid confusion that ' s what this s tandard should say. COMMITrEE ACTION: Accept in Principle. CO MMITrEE STATEMENT: Revisions accepted for paragraph 2-9.3.1 will require the use of listed controllers in all cases. This should satisfy the in tent of the submitter.

N F P A 750 - - A 9 6 R O P


AFFIRMATIVE: 29 ABSTENTION: l

EXPLANATION OF ABSTENTION: GIOSEFFI: See my Explanat ion of Abstention on 750-I (Log #4).

(Log #2) 750- 26 - (2-10.1.2 Exception): Reject SUBMITTER: J o h n J . Walsh, Uni ted Association RECOMMENDATION: Add "because of risk" to "occupants". SUBSTANTIATION: The exception as written is too loose. Systems should be automat ic unless there is avery good reason for t h e m no t to be. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: There may be o ther condit ions or situations where manua l operat ion is preferable, o ther than if it poses a risk to die occupants. Manual operat ion may also be preferable in unoccup ied spaces such as process areas or test enclosures. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #43) 750-27- (2-10.2.1): Accept in Principle SUBMITTER: Paul H. Dobson, Factory Mutual Research Corp. RECOMMENDATION: The NOTE shou ld be deleted or clarification provided. SUBSTANTIATION: It is no t clear as to what shou ld be done, i.e., if a cross zoned system is used shou ld the spacing between detectors be reduced 50 percent of the required spacing to take into account the slower response time. From descript ions of water mist systems delay in actuat ion of the system does not seem to reduce their effectiveness; larger fires seem to be control led more quickly than smaller fires. COMMITrEE ACTION: Accept in Principle• COMMITTEE STATEMENT: The "Note" has been placed in the appendix as an informational item. The Technical Commit tee intends to allow for various detect ion systems and configurat ions (spacing, orientat ion) to be used. The limiting factor should be "Can the detect ion system, no mat ter what type, activate the water mist system in a satisfactory t ime to control the fire?" This will be governed by the listing. This should clarify the in tent of this section and satisfy the concern of the submit ter . NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITrEE ACTION:



(Log#71) 750- 28- (2-10.2.1): Accept in Principle SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: Automat ic detect ion shall be in accordance with NFPA 72E. SUBSTANTIATION: Detection and trouble should be governed by a s tandard d o c u m e n t like it is for halon, CO 2, etc. It shou ld not be listed in here. All detect ion system should conform to NFPA 72E and no restriction or exception should be listed in this document . COMMITrEEACTION: Accept in Principle. COMMITTEE STATEMENT: A revision has been accepted for paragraph 2-10.2.1. The detect ion system is to be installed in accordance with NFPA 72, National Fire Alarm Code. In addition, it is i n t ended that the detection system utilize listed equipment . NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



655

(Log #72) 750- 29- (2-10.2.2): Reject SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: Standby requi rements should be referred to NFPA 72E. SUBSTANTIATION: Refer to substant iat ion of 2-10.2.1. COMMITrEE ACTION: Reject. COMMITrEE STATEMENT: NFPA 72, as referred to in 2-10.1.1 and 2-10.2.1 does stipulate these provisions. Mandat ing tha t detect ion and alarm systems conform to NFPA 72 will result in specific provisions for s tand by power to be included. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: GIOSEFFI: See my Explanation of Abstent ion on 750-I (Log #4).

(Log #73) 750- 30 - (2-10.4.2.1): Reject SUBMI'I ' rER: Pierre Girard, Securiplex Inc. RECOMMENDATION: The last sentence of dlis pa ragraph should be rephrased as follows: "Pneumat ic control lines normally pressurized and used as part of the system actuat ion shall be supervised." SUBSTANTIATION: Securiplex water spray system include un pressurized, pneumat i c . . . . lines which wilIbe piressurized only upon system actuauon. Supervising u n p r e s s u n z e d lines would be unpractical. COMMITrEE ACTION: Reject. COMMITTEE STATEMENT: There is a need to still supervise some lines which do no t normally have pressure on them, but which are crucial to system operation. This paragraph (now paragraph 2- 10.4.3.1) is applicable to any pneumaffc lfne used as a part-of the system actuation. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF NEGATIVE: CHARNEY: The r equ i r emen t that all pneumat i c control lines, used

as part of system actuation, shall be supervised (whether normally pressurized or not) is overly restrictive and arbitrary.

Several o ther well established special hazard NFPA standards specifically address pneumat i c control equ ipmen t and do no t require supervision of the pneumat i c actuation lines. These include:

NFPA 2001 (1994 edition) paragraph 2-3.4.2. NFPA 17 (1994 edition) paragraph 3-7.2. NFPA 12A (1992 edition) paragraph 2-3.4.2. In addition, several examples of h igh risk, h igh hazard applications

that use unsupervised pneuma t i c control systems include: • Navy Halon Systems: These systems use remote pneumat i c

control lines as the primary means of actuation. These pneumat i c lines are not supervised.

• Alaska Pipeline (North Slope) Halon 1301 systems: These systems use unsupervised pneumat i c actuat ion lines.

• USCG approved CO 2 and Halon 1301 systems: These systems allow the use of unsupervised pneumat i c control lines for both remote and local actuation.

The above informat ion provides sufficient historical background to justify that the manda to ry r equ i r emen t for supervised pneumat i c systems is no t necessary and should be deleted. • DINENNO" Requir ing supervision . . . . . of unpressur ized pneumat i c

hnes used in ac tuauon ts excessive and dlogacal. For example, we do not require supervision of open nozzle piping, which is critical to the successful operation of the system. Agent supplies or pressurant levels do not require supervision in o ther special hazard systems. These are clearly requi red for successful system operation. Many of the concerns can be r emed ied by proper inspect ion frequencies. EXPLANATION OF ABSTENTION:


(Log #44) 750- 31 - (3-1.2 (New)): Reject SUBMITTER: Paul H. Dobson, Factory Mutual Research Corp. RECOMMENDATION: system water supply - - private water supply, or dedicated fixed tank (s).' For ded ica tedf ixed tank - -

~ ressu rization. UBSTANTIATION: Dedicated is a term that is more descriptive of

the purpose of the tank i.e., the tank will be dedicated to providing the water supply for the water mist system.

N F P A 7 5 0 1 A 9 6 R O P

COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: It is permissible to utilize o ther than a dedicated tank in some circumstances. While certain systems may come with their own captured water supply, o ther systems may rely on c o m m o n water storage facilities which may supply o ther water based fire protect ion systems or non-fire protect ion uses. The latter type of tank would presumably be a r ranged with a reserve supply for fire protection uses only. It is no ted that details on water supply sources and a r r angemen t s are n o w g o v e r n e d in Chapter 7. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #74) 750- 32 - (3-2, 3-3, 3-4): Accept in Principle SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: Section 3-2, 3-3 and 3-4 should all be included in the c o m m o n Section 3-1 titled "Single Fluid Water Mist System." SUBSTANTIATION: These three sections basically talk about the requ i rements for simple sprinkler systems. None of these paragraphs are describing in relation to the twin fluid water mist system and Securiplex system should not have to conform to these section. COMMITTEE ACTION: Accept in Principle.

Section 3-2 has been revised to describe and discuss system application features such as local application, total c o m p a r t m e n t application and zoned application. Operat ional features are now in Section 3-4. COMMITTEE STATEMENT: See revised Sections 3-2 and 3-4. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: GIOSEFFI: See my Explanation of Abstenlion on 750-1 (Log #4).

(Log #25) 750- 33 - (3-3): Accept SUBMITTEI~ Jack Davis, Sprinkler Fitters U.A. Local 483Join t

rent iceship Commit tee OMMENDATION: New 3-3.1 General.

3-3.1 r e n u m b e r to 3-3.1.1. SUBSTANTIATION: Editorial. COMMITTEE ACTION: Accept.

This correction applied to the working draft. Dur ing the final round of changes, dais section has been entirely deleted. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #9) 750- 34- (3-3.1): Reject SUBMITTER: J o h n J . Walsh, Uni ted Association RECOMMENDATION: Delete everything after the word "installed". SUBSTANTIATION: Unless the vo lume is very small, grids should no t be permi t ted because of the t ime delay in gett ing water to the nozzles. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: This is a p e r f o r m a n c e element , f f a system has been evaluated for use on a dry pipe grid configuration, then it should be permit ted. Due to the typically small d iameters associated with water mist system, it is likely that the system pipe volumes will be relatively small. It is no ted that this system

PuMBerational m e t h o d is now regulated by Section 3-4.4. ER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30

VOTE ON COMMITTEE ACTION: AFFIRMATIVE: 29 ABSTENTION: 1

EXPLANATION OF ABSTENTION: GIOSEFFh See my Explanat ion of Abstention on 750-1 (Log #4).

656

(Log #26) 750- 35 - (3-3.1.2 (New)): Reject SUBMITTER: Jack Davis, Sprinkler Fitters U.A. Local 483Joint A~Erenticeship Commit tee

OMMENDATION: New 3-3.1.2 to read: Only water mist systems with filters or strainers on the supply side

of the dry pipe valve shall be permitted. SUBSTANTIATION: Ice crystals f rom condensa t ion or residual moisture f rom system operat ion and test ing could freeze in the filter m e d i u m prevent ing water f rom reaching the nozzle. Paragraph %6.1 requires filter m e d i u m openings 33% of m i n i m u m orifice d imension. The small m e d i u m openings will easily retain moisture that will freeze. Requir ing the filter to be on the supply side of the dry pipe ~alve would prevent freezing. COMMITI'EE ACTION: Reject. COMMITI'EE STATEMENT: Requi rements for strainers and filters are now governed by Sections 4-7 and 7-6.1. Section 7-6.1.3 requires the filter or strainer to be installed on the system side of all piping which is no t corrosion resistant. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #10) 750- 36 - (3-3.3.1): Reject SUBMITTER: J o h n J . Walsh, Uni ted Association RECOMMENDATION: Add a sen tence to read:

"In no case shall the m a x i m u m o p a c i t y exceed gallons. SUBSTANTIATION: The s t a n d a r d s h o u l d provide guidance to the testing labs in the form of a not to exceed point. I lack the expertise to r e c o m m e n d the specific point. COMMITI'EE ACTION: Reject. COMMITTEE STATEMENT: See the Commit tee Action on 750-37 (Log # 27). NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #27) 750- 37 - (3-3.3.1): Reject SUBMITTER: Jack Davis, Sprinkler Fitters U.A. Local 483Join t

rent iceship Commit tee OMMENDATION: The m a x i m u m capacity of a dry pipe system

shall be l imited to the systems ability to deliver water to the most hydraulically remote nozzle in less than ?? seconds u p o n activation of that nozzle. SUBSTANTIATION: The reason for volume limitations in dry pipe systems is a p roduc t of NFPA 13's concern for the t ime delay created by the discharge of residual compressed air t h rough a s tandard 1/2" orifice. Water mist systems will have nozzle orifice sizes considerably smaller and will vary f rom manufac tu re to manufac ture . This paragraph should redirect its at tent ion f rom volume to the original considerat ion of elapse time. CO MMITrEE ACTION: Reject. COMMITI'EE STATEMENT: The Technical Commit tee does not have any data to de te rmine what the value should be. It is ant icipated tha t as informat ion becomes available, it may be possible to specify a value at some poin t in the future. It is no ted that specific limits (p ip ingvo lume) are no longer considered by NFPA 750. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE O N COMMITTEE ACTION:



(Log #28) 750- 38 - (3-3.5.3 (New)): Reject SUBMITTER: Jack Davis, Sprinkler Fitters U.A. Local 483Join t

~ prent iceship Commit tee OMMENDATION: Insert the following text as a new 3-3.5.3.

R e n u m b e r Section 3-3.5 accordingly. 3-3.5.3 W h e n a dry pipe system supplies a freezer box file air

supply shall:

N F P A 750 - - A 9 6 R O P

1. Dehumidify the compressed air that is suppl ied to the water mist system so tha t its pressure dew point is 20 degrees Fahrenhei t below the normal freezer tempera ture .

2. Feed die compressed air into d i e f r eeze r water mist pipes th rough separate lines which can be easily removed for inspect ion and cleaning. And, el iminate the compressed air input ju s t above the Dry Pipe Valve.

3. Install a check valve (with a bleed hole in the clapper) above the Dry Pipe Valve to prevent moisture f rom the Dry Pipe Valve pr iming water f rom e n t e r i n g t h e Water Mist system piping. SUBSTANTIATION: ]'lie format ion of ice due to condensa te form compressed air is a considerat ion of NFPA 13 and Factory Mutual. This s tandard should also address the problem.

Note: Suppor t ing material is available for review at NFPA Headquarters . COMMr[TEE ACTION: Reject. COMMITTEE STATEMENT: See die Corrtmittee Action on 750-37 (Log #27). NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: GIOSEFFh See my Explanation of Abstention on 750-1 (Log #4).

(Log #29) 750- 39 - (3-4.1.2.1 (New)): Accept in Principle SUBMITTER: Jack Davis, Sprinkler Fitters U.A. Local 483Join t

rent iceship Commit tee OMMENDATION: Add a new 4-4.1.2.1.

4-4.1.2.1 The manua l release shall be located in plain sight at the location of the valve it controls. SUBSTANTIATION: This manua l release valve is for emergency

Urposes and wording is required to insure that it is properly cated.

C O M M I T r E E ACTION: Accept in Principle° C O M M I T r E E STATEMENT: Requi rements for manua l actuation have been relocated to Section to 4-9.4. Sections 4-9.4.1 and 4-9.4.2 accomplish what is i n t ended by the submit ter . NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #30) 750- 40 - (3-4.2.2): Reject SUBMITTER: Jack Davis, Sprinkler Fitters U.A. Local 483Join t Apprent iceship Commit tee RECOMMENDATION: Revise to read: Size of systems. The m a x i m u m size o f a preaction system shall be l imited to the Water Mist systems ability to deliver water to the most hydraulically remote nozzle in less than ?? seconds u p o n activation of tha t nozzle with normal supervisory air pressure. SUBSTANTIATION: ~Ille reason for size limitations in preaction systems is a p roduc t of NFPA 12's concern for the t ime delay created by the discharge of residual compressed air t h rough a s tandard 1 /2 in. orifice. Water mist systems will have nozzle orifice sizes considerably smaller mad will vary f rom manufac tu re to manufacture . This paragraph shou ld redirect its at tent ion f rom size to the original considerat ion of elapse time. COMMIq[TEE ACTION: Reject. COMMI'['rEE STATEMENT: See die Commit tee Action on 750-37 (Log #27). NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #3) 750- 41 - (3-4.2.3): Accept in Principle SUBMITI'ER: J o h n J . Walsh, Uni ted Association RECOMMENDATION: Delete everything after the word supervised. SUBSTANTIATION: Size is no t a de t e rminan t of value I quest ion if

rinkler system rules are applicable in this case. MMITI 'EE ACTION: Accept in Principle.

COMMITTEE STATEMENT: See the Commit tee Action on 750-42 (Log #45).




(Log #45) 750- 42 - (3-4.2.3): Accept in Principle SUBMITTER: Paul H. Dobson, Factory Mutual Research Corp. RECOMMENDATION: Supervision. W a t e r mist Diping and fire detect ion systems shall be automatically supervisea~d.c, l t , , o ~ d t ~ ~ o~ ca , , f ~i f: as reouired bv the Authori ty Having lurisdictjorl. SUBSTANTIATION: There are many factors which s'h~ould be taken into considerat ion when de te rmin ing whether supervision is needed. Loss expectancy and life safety considerat ions would also be factors. The factors could be listed but in the end it would be die Authori ty Having Jurisdict ion that would make the decision. COMMITTEE ACTION: Accept in Principle.

Requi rements for supervision of select system componen t s are governed by Chapters 4 and 7. COMMITI?EE STATEMENT: See Sections 4-9.2.3, 7-6.3.1, 7-6.4.1 and 7-7.1.2. Specific e lements and componen t s are now required to be supervised. This basically eliminates the need to consider the size of the system or o ther factors. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #5) 750- 43 - (3-5.5): Accept in Principle SUBMITTER: J o h n J . Walsh, Uni ted Association RECOMMENDATION: Delete the words "or approved". SUBSTANTIATION: Valves control l ing the flow to nozzles require listing. COMMITrEE ACTION: Accept in Principle. COMMITrEE STATEMENT: Various port ions of the d o c u m e n t have been revised to require critical e q u i p m e n t to be listed. The r equ i r emen t for listing of these valves is now conta ined in Section 4- 8.1.3. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



750- 44- (3-5.7): Reject (Log #75) SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: This paragraph shou ld read: "Where air is the atomization or pressurizing fluid, an automat ic m e a n s shall be provided to avoid a discharge within the network when the full condit ion of the water supply tank is no t m e t " SUBSTANTIATION: Securiplex' interlock system for a low water cut-out operates in a different manner . The float valve located at the top of the water vessel impedes a water /a i r discharge if a safe water level is no t seen and initiates the sequence only knowing that there will be e n o u g h water for the prescribed durat ion. The system does no t abor t in the middle of a sequence is it detects low water. By ensur ing a full tank and following proper design constrains, the air supply will be exhaus ted prior to the water supply. COMMITI'EE ACTION: Reject. COMMITrEE STATEMENT: The Technical Commit tee is of the opinion that the cur ren t text covers the situation. Section %6.4.1 requires tank levels to be supervised. W h e n water levels are below op t imum or m i n i m u m levels, the a larm devices will notify the occupants of the problem. In addition, this section has been deleted f rom the text. This would also be covered by revised 4-2.1. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



657

N F P A 750 ~ A96 R O P

(Log #76) 750- 45 - (3-5.10): Reject SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: This article should be g rouped with Article 3-5.8 and should read: "The atomizing and pressurization fluid supply shall be electrically supervised. This electric means could also ser¢ice t h e p u r p o s e of de tec t ing system activation." SUBSTANTIATION: The same electric means could serve the dual purpose of supervising a leak in the a tomizing media and of detect ing system activation. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: NFPA 72 does no t permi t a single device to serve both a supervisory and alarm capacity. Supervisory criteria for system status or equ i pmen t status relating to tlae water supplies and the atomizing media are governed in Chapter 7. Supervision is to be accompl ished in accordance with NFPA 72. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: GIOSEFFI: See my Explanation of Abstention on 750-1 (Log #4)~

(Log #11) 750- 46 - (4-2 Exception (New)): Reject SUBMITTER: J o h n J . Walsh, Uni ted Association RECOMMENDATION: Add an Exception to read:

"A water mist system shall no t be listed for an area in excess of _ _ sq ft." SUBSTANTIATION: The s tandard should provide guidance to file testing labs in the form of a not to exceed point. I lack the expertise to r e c o m m e n d the specific point. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The Technical Commit tee does not see a justification to limit systems by area or by volume. The evaluation and subsequen t listing of a system package, or of the individual components , would reveal any such limitation. Section 5-2.1.1 requires an evaluation of the size (area a n d / o r volume) of the hazard which is i n t ended to be protected. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: GIOSEFFh See my Explanation of Abstent ion on 750-1 (Log #4).

(Log #46) 750-47- (4-3.1): Accept in Principle SUBMITTER: Paul H. Dobson, Factory Mutual Research Corp. RECOMMENDATION: General. Water mist nozzles shall be installed in accordance with their listing. Delete or clarify tile rest of the p a r a ~ a p h and the Exceptioo. SUBSTANTIATION: The rest of Paragraph 4-3.1 seems to repeat informat ion tha t is conta ined in Paragraph 4-3.3 "Nozzle Spacing and Location". COMMITTEE ACTION: Accept in Principle. COMMITTEE STATEMENT: The Technical Commit tee appoin ted a special Task Group to evaluate dais criteria. The specific e lements have been placed in Section 2-6.1 and A-2-6.1. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #77) 750- 48 - (4-3.3): Reject SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: The paragraph should simply state that the location and spacing of the nozzle is done based on per formance tests and as per the approved design manual . SUBSTANTIATION: Performance tests are specifically conduc ted to de te rmine these two parameters , in order to achieve fire ex t inguishment . Since we are deal ing with a new technology, it is no t known at this stage if the system will behave the same way in different fire scenario if the same spacing and location of nozzle is kept. COMMIT~'EE ACTION: Reject.

658

COMMITTEE STATEMENT: The Technical Commit tee is unclear on how m u c h of 4-3.3 the submit ter wishes to delete f rom this section. Nozzle spacing and posi t ioning criteria are now governed by Section 4-2. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #78) 750- 49 - (4-4.1.1): Accept in Principle SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: Replace "all automat ic sources" with "all external sources". SUBSTANTIATION: Securiplex water mist system was originally des igned as a s tand alone system, i.e. there is no external source of air a n d / o r water that need to be controlled. There are no need for control valves on a s tand alone system° There are no shu t offvalves, m u c h like a high pressure CO 2 system. COMMITTEE ACTION: Accept in Principle.

The basic requi rements for control valves has been relocated to Section 4-8.1.6. An exception has been included in this port ion of the text to address the situation contempla ted in this proposal. COMMITTEE STATEMENT: See the revision to Section 4-8.1.6. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #79) 750- 50- (4-4.1.2): Accept in Principle SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: This s h o u l d b e "as required". " SUBSTANTIATION: Securiplex water mist system was originally des igned as a s tand alone system, i.e., there is no external source of air a n d / o r water that need to be controlled. COMMITrEEACTION: Accept in Principle. COMMITTEE STATEMENT: See Commit tee Action on 750-49 (Log #78). NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #31 ) 750- 51 - (4-4.1.4): R e j e c t SUBMITTER: Jack Davis, Sprinkler Fitters U.A. Local 483Join t

~ Pcrenticeship Commit tee OMMENDATION: Revise to read: A test connect ion as

described in paragraph 4-6.1.3 shall be provided on all preaction systems. SUBSTANTIATION: A means to test and record the elapse t ime for water delivery to the most remote head for preaction systems should be provided. COMMITTEE ACTION: Reject. COMMY['rEE STATEMENT: No text is included at this t ime with respect to a test connect ion. While it may be necessary to accommoda te some type of flow testing, that issue has not been completely resolved as of now. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #80) 750- 52 - (4-4.2): Accept in Principle in Part SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: This section shou ld be titled "Water Pressure Regulat ing Valves" SUBSTANTIATION: This section should no t be used for an air pressure regulator used to downgrade the air pressure.

N F P A 750 1 A 9 6 R O P

COMMITTEE ACTION: Accept in Principle in Part. Section 4-8.3 now governs Pressure Regulat ing Devices. Section

4-8.3.1 has been des ignated to cover water pressure regulat ing valves while Section 4-8.3.2 has been des ignated to cover air pressure regulat ing valves. COMMIT'I'EE STATEMENT: See the revisions to section 4-8.3. • This should satisfy the in tent of the submitter. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: GIOSEFFI: See my F~xplanation of Abstention on 750-1 (Log #4).

(Log #32) 750- 53 - (4-4.2.5 (New) l: Accept in Principle SUBMITTER: Jack Davis, Sprinkler Fitters U.A. Local 483Joint Apprent iceship Commit tee RECOMMENDATION: Add a new 4-4.2.5 to read:

A flow test valve sized to produce the des igned flow of the pressure reducing valve shall be installed on the downst ream side of the PRV. SUBSTANTIATION: Most PRV's are field ad jus~ble and should be verified as to correct operation. A means to test the residual pressure of pressure reducing valves is .needed" COMMrITEEACTION: Accept in Principle.

I Revise the new suggested text to read as follows: 4-&3.1.6 A water flow test valve sized to produce the des igned flow

of the pressure reduc ing valve shall be installed on the downsu 'eam side of the PRV. COMMITTEE STATEMENT: The proposed text is directed at a PRV which regulates flow of water. T he Technical Commit tee will develop supprelnental guidance for PRV' s which regulate airflow. Section 4-8.3bas been revised to provide requi rements for the devices. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: GIOSEFFI: See my F~xplanation of Abstention on 750-1 (Log #4).

(Log #33) 750- 54 - (44.2.6 (Newl): Accept in Principle SUBMITTER: Jack Da~s, Sprinkler Fitters U.A. Local 483Join t

~p rent iceship Commit tee COMMENDATION: Add a new 4-4.2.6 to read:

A sign shall be a t tached to tbe pressure reduc ing valve indicating the correct discharge pressure for static and residual pressures. SUBSTANTIATION: Pressure reducing valves are normally field adjusted and the specifications need to be pos ted for the valve. COMMII~I'EE ACTION: Accept in Principle.

This has been included in Section 4-8.3.1.7. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #34) 750-55- (4-4.5.1.4 (New)): Reject SUBMITTER: Jack Davis, Sprinkler Fitters U.A. Local 483Join t Aj~prenticeship Commit tee

COMMENDATION: Add a new 4-4.5.1.4 and r e n u m b e r Section 44.5.1 accordingly: Flow test connect ions, and drains that double as flow test connect ions, shall te rminate in a location that will accept the full flow at normal system pressure without damage to property or create local flooding. SUBSTANTIATION: Flow test connect ions that canno t be opened for full flow are of no value. COMMITrEE ACTION: Reiect. COMMITrEE STATEMENT: See the Commit tee Action on 750-51 (Log #31). NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #35) 750- 56 - (4-4.6.1 Exception): Reject SUBMITTER: Jack Davis, Sprinkler Fitters U.A. Local 483Join t

rent iceship Commit tee OMMENDATION: The except ion to 44.6.1 shou ld be deleted.

SUBSTANTIATION: The reference to antifreeze used in Water Mist systems should be avoided by dais s tandard. There is concern about the inhalation of water mist mixed with additives of all types. The exception may confuse someone into th inking that it is acceptable to add antifreeze solutions to a water mist system. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: At this point in time, water mist systems which utilize various types of additives will be considered by the US EPA unde r the SNAP program. Unless an EPA restriction is imposed, there is no reason for NFPA 750 to restrict the use of antifreeze solutions. It is no ted tha t dais paragraph has been deleted. It is no t in tended that anti-freeze systems be prohibited. System per formance parameters , as described in Section 5-1 could be evaluated with the use of anti-freeze solutions if desired. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: GIOSEFFh See my Explanation of Abstention on 750-1 (Log #4).

(Log #36) 750- 57- (4-4.6.2.2): Reject SUBMITTER: Jack Davis, Sprinkler Fitters II.A. Local 483Join t Apprent iceship Commit tee RECOMMENDATION: Delete the words "above g r o u n d level". SUBSTANTIATION: Seismic separat ions occur in buildings with basements and sub basements that are below actual g roundleve l . The words above g r o u n d level imply that if the seismic separat ion is below actual g round level it is no t a consideration. COMMITTEE ACTION: Reject. COMMITrEE STATEMENT: Seismic criteria has been deferred to NFPA 13 by Section 4-3.6, The Seismic Task Group for NFPA 13 does no t agree with the need to provide special provisions for seismic separat ion assemblies when installed below grade. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #47) 750- 58 - (4-5.2.1): Accept SUBMITTER: Paul H. Dobson, Factory Mutual Research Corp. RECOMMENDATION: Delete or clarify. SUBSTANTIATION: It is not clear what is mean t by "prepare the hazard area for discharge." COMMITrEE ACTION: Accept.

Delete the text. COMMI'VrEE STATEMENT: It is no ted that a part of the design objective criteria is to consider the impact of ventilation factors (see 5-2.1.2). NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #12) 750- 59 - (4-6.1.3): Reject SUBMITTER: J o h n J . Walsb, Uni ted Association RECOMMENDATION: I n t h e first sen tence change "to provide a flow equivalent to one nozzle of a type" with "giving the smallest nozzle area".

Add to the end of the paragraph, "The system design shall be such that water is delivered to the system test connect ion in not more than _ _ sec, start ing at the normal air pressure on the system and at the t ime of fully opened test connect ion." SUBSTANTIATION: I visualize these systems as being less forgiving of t ime delays than dry pipe sprinkler systems. There should be a specified m a x i m u m time f rom open ing of the test valve to discharge and the orifice in the test connect ion should be of the smallest size on the system.

659

N F P A 7 5 0 - - A 9 6 R O P

COMMITTEE ACTION: Reiect. COMMITTEE STATEMENT: See the Commit tee Action on 750-51 (Log#31) . NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #13) 750- 60 - (4-6.1.4): Accept in Principle SUBMITTER: J o h n J . Walsh, Uni ted Association RECOMMENDATION: Change "piping" to "priming". SUBSTANTIATION: Typo. COMMITrEE ACTION: Accept in Principle. COMMITrEE STATEMENT: This section has been deleted. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #48) 750- 61 - (5-2.2): Accept in Principle SUBMITTER: Paul H. Dobson, Factory Mutual Research Corp. RECOMMENDATION: Delete. SUBSTANTIATION: the oxygen available for combus t ion shou ld no t be a considerat ion when evaluating the fire hazard, unless one of the me thods is to inert the volume. COMMITrEE ACTION: Accept in Principle.

See the revisions for Section 5-2.1. COMMITI'EE STATEMENT: A substantial revision w~s made to Chapter 5. A n u m b e r of factors mus t now be evaluated including the c o m p a r t m e n t variables, ventilation factors, and fuel properties. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #49) 750- 62 - (5-2.2.2): Accept in Principle SUBMITTER: Paul H. Dobson, Factory Mutual Research Corp. RECOMMENDATION: Delete all bu t the last sentence. Revise the last sentence to read: A fire hazard analysis shall be used to de te rmine the type of system/act ivat ion device. The device selected should be based on tvoe of combustible, fire ~rowth rate. and exnected damage to b-uildin~ and contents, v S LTBSTANTIA'I'~I ON: Clarification. COMMI'I*rEE ACTION: Accept in Principle. COMMITrEE STATEMENT: The Technical Commit tee considers the system per formance to include supplementa l detect ion systems in some ins-tances. T he response of a detect ion system, when used to activate the mist system, is an integral part of the system and will impact on the efficiency and per formance of the system. Overall evaluation of the system as described in Section 5-1 includes an evaluation of the total system per formance inc luding activation of the system. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #50) 750- 63 - (5-2.2.2.1): Accept in Principle SUBMITTER: Paul H. Dobson, Factory Mutual Research Corp. RECOMMENDATION: Delete or define "system efficiency". SUBSTANTIATION: If the system is listed for the particular application do not unde r s t and why the te rm "system efficiency" is needed. However, if it is n e e d e d it shou ld be defined. COMMITTEE ACTION: Accept in Principle. System efficiency will be deleted f rom the text. An appendix

discussion will be proposed to explain the in tent of dais section. COMMITTEE STATEMENT: See revisions to Sections 5-2.1, 5-2.2, and 5-2.3.

NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #81) 750- 64- (5-3): Accept SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: Section number s are mistyped. SUBSTANTIATION: Editorial. C O M M I T r E E ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #82) 750- 65 - (5-3.1.2): Accept in Principle SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: The last port ion of the paragraph should read: ".. .detection system or initiating device." SUBSTANTIATION: Securiplex water mist system could be actuated in various ways. The term "initiating device" does no t limit the actuat ion means. COMMITTEE ACTION: Accept in Principle. COMMITTEE STATEMENT: Operat ional characteristics of the system nozzles are now governed by Sections 3-3 and 3-4. See the new wording for these paragraphs . NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log#51) 750- 66 - (5-3.2.3, 5-3.2.3.1): Reject SUBMITTER: Paul H. Dobson, Factory Mutual Research Corp. RECOMMENDATION: Delete. SUBSTANTIATION: Repeats material that is covered earlier in the chapter. Section 5-3.2.3 is covered u n d e r 5-2.1.2. Section 5-3.2.3.1 is covered u n d e r 5-2.3. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The Technical Commit tee in tended to describe some general criteria which shou ld always be considered. The i tems in Section 5-3 are in t ended to be specific issues for specific types of system configurat ions and designs. This criteria is now required to be evaluated for all systems as described in Section 5-2. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VO TE ON COMMITTEE ACTION:



(Log #52) 750- 67- (5-3.5, 5-3.5.1): Accept in Principle SUBM]TTER: Paul H. Dobson, Factory Mutual Research Corp. RECOMMENDATION: Delete. SUBSTANTIATION: The informat ion addressed in these sections F8maears to be adequately covered in Section 7-3.

"ITEEACTION: Accept in Principle. COMMITTEE STATEMENT: Water supply dura t ions are specifically governed by Chapter 7. Part of the overall evaluation of the system per formance is considerat ion of the total water supply. See revisions for Section A-5-3.3.3 and Chapter 7. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE O N COMMITTEE ACTION:



660

N F P A 750 - - A96 R O P

(Log #53) 750- 68 - (5-4): Accept in Principle SUBMITTER: Paul H. Dobson, Factory Mutual Research Corp. RECOMMENDATION: Change "Approval Testing" to "Listing R~usir e m e n ts"

TANTIATION: "i'he tests required under this section are more consistent with wbat would be de te rmined during listing of the water mist system than with what and Authority HavingJurisdlction or user would be expected to determine. COMMITI'EE ACTION: Accept in Principle. COMMITTEE STATEMENT: Section 5-3 now addresses "Listing Testing" which is more descriptive of what is in tended by the overall system evaluations. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #37) 750- 69 - (5-4.3.2 (New)): Reject SUBMITTER: Jack Davis, Sprinkler Fitters U.A. Local 483Joint l~Erent icesh ip Committee

OMMENDATION: Insert new 5-4.3.2. Renumber Section 5-4.3 accordingly.

5-4.3.2 System Discharge Time. /L The elapse time upon opening the test connect ion to

stabilization of water flow at the test connect ion for preaction and dry systems.

B. The elapse time from activation of the water control valve to application of water mist on the hazard for f looding (deluge) systems. SUBSTANTIATION: The elapse time would be a prime concern for preaction systems, dry pipe systems, and deluge systems. COMMITTEE ACTION: Reject. COMMITrEE STATEMENT: See the Committee Action on 750-51 (Log #31). NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #54) 750- 70- (5-5, 5-5.1): Accept SUBMITTER: Paul H. Dobson, Factory Mutual Research Corp. RECOMMENDATION: Delete. SUBSTANTIATION: Both paragraphs appear to cover material which has been covered before in the same chapter in greater detail. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #83) 750- 71 - (6-2): Reject SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: Replace "(Intermediate and High Pressure System)" with "(Twin Fluids, Intermediate and High Pressure System)". SUBSTANTIATION: Both air and water piping network can be calculated using Darcy-Weisback calculation me thod regardless of the operating pressure. COMMITrEEACTION: Reject. COMMITTEE STATEMENT: The Committee is of tiae opinion that this is already covered. The Hazen-Williams formula is permi t ted for water calculations for a low pressure system regardless i f it is twin fluid or single fluid. For other systems or fluids, Darcy-Weisbach is the default-calculation procedure. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #55) 750- 72 - (6-2.1): Accept SUBMITTER: Paul H. Dobson, Factory Mutual Research Corp. RECOMMENDATION: The sentence refers to a formula to de t e rminep ipe friction losses but the formula is not given. SUBSTANTIATION: Clarification. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITI'EE ACTION:



(Log #56) 750- 73 - (6-2.1, 6-3.2): Accept SUBMIq['I'ER: Paul H. Dobson, Factory Mutual Research Corp. RECOMMENDATION: Use different symbols for weight density of fluid (6-2.1) and for frictional resistance in psi foot of pipe (6-3.2). SUBSTANTIATION: Clarification. COMMITFEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #57) 750- 74 - (Table 6-3.6.1): Accept SUBMITTER: Paul H. Dobson, Factory Mutual Research Corp. RECOMMENDATION: In the first column under fitting/Valve Diameter- three lines are labeled 1. They should be correctly labeled. SUBSTANTIATION: Clarification. COMMrITEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITrEE ACTION:



(Log #84) 750- 75 - (6-4.1 (New)): Reject SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: Pipe friction losses shall be de termined on the basis of the following formula:

Z~ Was = Pl * ( 1 -~/( 1 " 2 * A P u / P l ) . . . . . . wher~ APwas~ is the pressure d r o p . . i n a c o m .pressiole now. anct zxr u is file pressure drop in the same flow If it was mcompresslble as per Section 6-2. SUBSTANTIATION: The Darcy-Weisback method may be used for compressible air flow, in this modified form. COMMITrEE ACTION: Reject. CO MITrEE STATEMENT: The proposal simply provides a formula. This section must be expanded to include a calculation methodology of which such an equation may be a par t of. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #85) 750-76- (7-1.2): Accept in Principle SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: The article should read: "Compressed gas or other atomizing medium, when used as part of a twin fluid water mist system, shall not be supplied without water." SUBSTANTIATION: We cannot run air without water but can run water without air.

I COMMITTEE ACTION: Accept in Principle. Revise the language and place it in the Appendix as follows: A-7-1.2 Although some water discharge may continue after the

atomizing medium has been exhausted, it will not be effective for fire suppression.

661

N F P A 750 - - A 9 6 R O P

COMMITTEE STATEMENT: The appendix i tem addresses tbe concern associated with deplet ion of the a tomizing med ium. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: GIOSEFFh See my Explanat ion of Abstent ion on 750-1 (Log #4).

(Log #86) 750- 77- (%2.1): Reject SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: The s ta tement should be p receded by "In the case of total f looding systems, pressure.. ." SUBSTANTIATION: This s t a tement should no t be applied for a local application system. We suggest that a m i n i m u m safe distance of the protec ted e q u i p m e n t shou ld be given for the location of the air and water source. COMMITTEE ACTION: Reject. COMMITI'EE STATEMENT: The protected area will no t always consist of an enclosure. The m i n i m u m safe distance is likely to vary with the hazard or e q u i p m e n t protected and shou ld be reviewed by the authori ty having jurisdiction. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #87) 750- 78 - (7-4): Accept in Principle SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: For pre-engineered systems, m i n i m u m dura t ion shall be in accordance with the listing for the application in tended. SUBSTANTIATION: We cannot run air without water but can run water without air. COMMITTEE ACTION: Accept in Principle.

Revise Exception No. 1 to address the situation for pre-engineered systems. COMMITTEE STATEMENT: See the revised text for paragraph 7-4, Exception No. 1. Also, see the Commit tee Action on 750-80 (Log #15). NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #14) 750- 79 - (7-4 Exception No. 1): Reject SUBMITTER: J o h n J . Walsh, Uni ted Association RECOMMENDATION: Insert between the words "systems and shall" the following:

"designed to protect equ i pmen t or o ther special hazards in unoccup ied areas." SUBSTANTIATION: The in tent should be in the body of the s tandard where it is b inding not informational . COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The 30 minu te dura t ion is no t exclusively tied into life safety concerns. In addit ion, it was no t in tended by the Technical Commit tee tha t the occupiable / unoccupiable criteria be the only considerat ion. Systems can be used in occupied spaces with dura t ions of less than 30 minutes when the system is listed for lower durations. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE O N COMMITTEE ACTION:


EXPLANATION OF ABSTENTION: GIOSEFFh See my Explanat ion of Abstention on 750-1 (Log #4).

(Log #15) 750- 80 - (7-4 Exception No. 1): Accept in Principle SUBMITTER: J o h n J . Waish, Uni ted Association RECOMMENDATION: Add "But never less than rain." SUBSTANTIATION: The s tandard should provide guidance to the testing labs in the fo rm of a m i n i m u m poin t which cannot be passed. I lack the expertise to r e c o m m e n d that point. COMMITTEE ACTION: Accept in Principle. COMMITTEE STATEMENT: See the Commit tee Action on 750-78 (Log #87). NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #16) 750- 81 - (7-4 Exception No. 2): Reject SUBMITrER: J o h n J . Walsh, Uni ted Association RECOMMENDATION: Add "But not less than the absolute m i n i m u m specified in Exception 1 for unoccup ied space nor _ _ rain for occupied spaces." SUIKSTANTIATION: The s tandard should provide guidance t.o the testing labs in the form of m i n i m u m points tha t canno t be passed. This proposal is t ied to my proposal to modify Exception No. 1. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The Technical Commit tee does not want to impose a lower limit on the dura t ion at this poin t in time. As more informat ion on system per formance and capability comes along, it may be possible to impose such a limit in the future. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #88) 750- 82 - (7-6.1): Reject SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: This article shou ld read: "If the water supply is con tamina ted and contains particles in excess of 33% of m i n i m u m orifice d imension, a listed strainer or filler shall be

rovided on the supply side of the nozzle when required by Table 6.1.

SUBSTANTIATION: Portable, deionized or demineral ized water is used in the water mist system of Securiplex. The necessity of having a strainer is no t shared. We agree that water supplies f rom a p o n d or lake migh t be subject to impurities. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: Nei ther the Commit tee nor the system manufac tu re r can guarantee tha t the water supply will no t change or deteriorate after being placed in the storage cylinder. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #89) 750- 83 - (%6.1): Accept in Principle SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: A co lumn showing the protect ion measures for nozzle protection orifice between 300 micron and 3 m m should be added. SUBSTANTIATION: Complet ion. COMMITTEE ACTION: Accept in Principle.

Several revisions have been made to Table 7-6.1.2 (Formerly Table 7-6.1). COMMITTEE STATEMENT: The changes made to the Table now include those ranges of concern in the proposal. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



662

N F P A 7 5 0 - - A 9 6 R O P

(Log #90) 750- 84- (7-6.4): Accept in Principle SUBMITTER" Pierre Girard, Securiplex Inc. RECOMMENDATION: This article should not be made so general. SUBSTANTIATION: The NFPA 22, Standard for Water Tanks for Private Fire Protection is tk~r large above ground tanks. Securiplex water mist system does not include a small water tank which cannot be ruled by that standard. Such pressurized tank fall under the ASME Section 8 Pressure Vessel Code. COMMITTEE ACTION: Accept in Principle.

Larger water storage tanks are in tended to be governed by NFPA 22. Storage containers are in tended to be governed bySection %6.5. This is in tended to alleviate strict adherence to NFPA 22 for those smaller facilities. COMMITTEE STATEMENT: See the criteria proposed in Section 7-6.5. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #38) 750- 87- (8-1.2(r) (New)): Accept in Principle SUBMITTER: Jack Davis, Sprinkler Fitters U.A. Local 483Joint

renticeship Committee OMMENDATION: Insert new item (R) and reletter

accordingly Calculation of loads for sizing, and details of sway bracing for all

piping, storage tanks, and other related equipment. SUBSTANTIATION: The calculation of seismic loads should be included in the design of the system and indicated on the plans submitted for approval to the Authority Having Jurisdiction. COMMITTEE ACTION: Accept in Principle.

Revise the proposed item R as follows: "(R) The calculation of seismic loads if seismic restraint is required

by the authority having jurisdiction." COMMITTEE STATEMENT: The other elements suggested for this change are adequately covered by items (Q), (s) and (T). NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #17) 750-85- (7-7.1.1 Exception No. 1): Accept SUBMITTER: JohnJ . Walsh, United Association

i RECOMMENDATION: Delete. SUBSTANTIATION: The NFPA definition of authority having j.'urisdiction is too broad to allow delegation of a decision of this importance. COMMITrEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF NEGATIVE: PERKINS: As the author of the exception I would offer the

following rewrite of the exception to address the concerns of the authority having jurisdiction decision anthority in evaluating Water Mist System components .

Revised the Exception: Delete the words (of the Authority Having Jurisdiction) after the word "ap,l~roval'.

Add the words after the word ' approval" (of the manufacture). Comment: Removingthe exception disallows the end-user from

utilizing air supplies which meet or exceed the manufactures requirements providing that all the other exception requirements are met. EXPLANATION OF ABSTENTION:


(Log #91) 750- 86 - (7-7.1.2): Accept in Principle SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: The word "controlled" should be replaced by the word "supervised". SUBSTANTIATION: The water and air pressures may not be controllable, specially if they are stored. It is important to supervise the pressure, it should be noted that in the case of Securiplex's system, the water is stored at atmospheric pressure, thus, not requiring supervision of pressure. COMMITTEE ACTION: Accept in Principle. A revision was accepted for 7-7.1.2 (now identified as 7-7.1.4).

Supervision of specific equipment components and system portions is governed by paragraph 7-6.5. COMMITI'EE STATEMENT: The devices which regulate the pressure will be required t a be listed. This would include providing a means by which to moni tor the available airpressure. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #39) 750- 88 - (9-1 (c) (New)): Reject SUBMITTEP.= Jack Davis, Sprinkler Fitters U.A. Local 483Joint

renticeship Committee OMMENDATION: Add 9-1 (c):

Submit a completed and signed contractors material and test certificate. SUBSTANTIATION: A contractors signed materials and test certificate [see NFPA 13 fig 8-1 (a) and 8-1(b)] should be provided as an acknowledgment that materials and tests performed are in accordance with the requirements of this standard. Also test results can be used for comparison with test that may take place in the future. COMMrI'rEE ACTION: Reject. COMMITI'EE STATEMENT: The Technical Committee does not see the need for a test certificate at this point in time. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE O N COMMITTEE ACTION:



750- 89 - (9-2.2): Accept in Principle SUBMITTER: JohnJ . Walsh, United Association RECOMMENDATION: Reorganize as follows:

9-2.2.1 General. 9-2.2.1.1 Existing 9-2.2.3 9-2.2.1.2 Existing 9-2.2.3 (The number is repeated) 9-2.2.1.3 Existing 9-2.2.4 9-2.2.1.4 Existing 9-2.2.5 9-2.2.2 Low pressure system 9-2.2.2.1 Existing 9-2.2.1 %2.2.2.2 Existing9-2.3 9-2.2.3 Existing 9-2.2.2.

SUBSTANTIATION: Clarity by listing the items applicable to all systems first and then being system specific. COMMITI'EE ACTION: Accept in Principle. Accept the suggestion reorganization as submitted with one

exception. Retain Current Section 9-2.3 as a separate section. COMMITrEE STATEMENT: Air tests are limited to specific types of systems based upon the mode of operation of the system. NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 30 VOTE ON COMM1TFEE ACTION:



(Log #18)

663

N F P A 7 5 0 - - A 9 6 R O P

(Log #40) 750- 90 - (9-2.4.1.8 (New)): Reject SUBMITTER: Jack Davis, Sprinkler Fitters U.A. Local 483Join t Apprent iceship Commit tee RECOMMENDATION: Add new 9-2.4.1.8:

Pressure reducing valves when used shall be flowed at the des igned flow th rough the flow test valve provided by (New) 4-4.2.5. Static and residual pressure shall be record on the contractors material and test certificate [New 9-1 (c)]. SUBSTANTIATION: Most PRV's are field adjustable and should be verified as to correct operation. Also test results can be used for comparison with test that may take place in the future. COMMITI'EE ACTION: Reject. COMMITTEE STATEMENT: Paragrapb 9-2.6 requires flow testing of systems when feasible. Such test ing would subject these valves to the necessary flow conditions. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #41 ) 750- 91 - (9-2.4.1.9 (New)): Reject SUBMITTER: Jack Davis, Sprinkler Fitters U.A. Local 483Join t l~j~Pcrenticeship Commit tee

OMMENDATION: Add new 9-2.4.1.9: All valves that are control led hydraulically, pneumatically, or

electrically shall be exercised using the design m e t h o d of operat ion. The correct operat ion of each valve shall be verified and recorded on the contractors material and test certificate. SUBSTANTIATION: The verification of operat ion of all automatically control led fire protect ion valving is essential to system operation. COMMITTEE ACTION: Reject. COMMITI'EE STATEMENT: Paragraph 9-2.6.3 currently governs operational testing of these valves.. T he Technical Commi t tee does not see a benefi t in adding dais addit ional language. NUMBER OF COMMITTEE MEMBERS ELI~.IBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



SUBSTANTIATION: The actual inspection f requency will apply if the air source for the water mist system is exterior to the system an d cannot be moni to red at all t ime. In the case of a self contained unit, we do no t feel that the inspect ion could be done on a weekly basis to verify the air source. We are deal ing with a high pressure source s tored in a cylinder which is, in turn, mon i to red against leaks by a pressure switch. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #58) 750- 94- (10-3.7 (New)): Accept in Principle SUBMITTER: Paul H. Dobson, Factory Mutual Research Corp. RECOMMENDATION: 10-3.7 After each operation, open water - mist nozzles shall be removed and the spray nozzle and its screen (if applicable) shall be cleaned, unless observation u n d e r flow condit ions indicates this is no t necessary. SUBSTANTIATION: The above is a modificat ion of the last sentence of Section 6-2.8 of NFPA 15 "Water Spray Fixed Systems for Fire Protection". This examinat ion is n e e d e d to assure that con taminants in the water supply do no t plug the nozzle or its screen mad prevent p roper future operat ion. COMMITrEEACTION: Accept in Principle.

Revise several section in 10-3 as follows: 10-3.7" After each system operation, a representat ive sample of

operated water mist nozzles in the activated zone shall be inspected. 10-3.8. After each system operat ion due to fire, the system filters

and strainers shall be cleaned or replaced. A-10.3.7 The representative sample shou ld include 10 percent of

the water mist nozzles in the activated zone. If contaminat ion of filters or s trainers are f ound on inspection, it is r e c o m m e n d e d tha t all nozzles with in the activated zone shou ld also be inspected. COMMIT]I'EE STATEMENT: This revised language establishes when nozzles should be inspected, what nozzles should be inspected and what percentage of noz-zles should be inspected at a given time. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TOVOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #92) 750- 92 - (Table 10-2(a)): Accept SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: Add footnote to "Air Pressure Cylinders" and "Water Tank".

Footnote: Where the air pressure and water levels are supervised by an automat ic fire detect ion and a larm panel, the f requency of inspection shall be l inked to tha t of the alarm and control panel. SUBSTANTIATION: Securiplex includes in this system a supervised pressure switch on the air cylinder(s) and a supervised level switch on the water tank. Since those devices will give a u-ouble alarm upon activation i.e. in case of a low air pressure in the air cylinder(s) and a loss of a minimal a m o u n t of water in the case of the water tank, it is no t felt that they should be inspected on a mon t h l y basis but on a semi-annually basis. COMMITTEE ACTION: Accept. COMMITrEE STATEMENT: T he Technical Commi t tee is interested in making addit ional revisions to this Table if supplementa l informat ion f rom the manufac ture rs isprovided. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #93) 750- 93 - (Table 10-2(b)): Accept SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: Add footnote to "Air Pressure Cylinders" and "Water Tank".

Footnote: Where the air pressure and water levels are supervised b y a n automat ic fire detect ion and alarm panel, the f requency of inspect ion shall be l inked to that o f the alarm and control panel.

(Log #95) 750- 95 - (Chapter 11 (New)): Accept in Principle SUBMITTER: Matthew T. Gustafson, US Coast Guard G-MTH-4 RECOMMENDATION:

I. Add a new chapter for mar ine installations with the following t e x t

CHAPTER 11 Water Mist Systems in Marine Applications 11-1 Systems on ships and vessels operat ing in a mar ine

env i ronmen t shall comply with the requ i rements of this chapter in addit ion to, or where applicable in lieu of, all o ther requi rements of this s tandard.

11-1-4.1 Definition. Listed. Equ ipmen t or materials inc luded in a list publ i shed by a

Listing Organizat ion acceptable to the Authori ty Having Jurisdiction. Listings shall state either tha t the e q u i p m e n t or materials mee t appropriate s tandards or have been tested an d found suitable for use in a specified manner .

Listing Organization. An organization tha t per forms all of the following: 1 ) develops and publishes p roduc t standards; 2) develops, publishes and conducts or controls p roduc t evaluation tests; 3 ) p e r f o r m s periodic inspect ion of p roduc t of listed eq u ip m en t or materials.

Marine Listed. Equ ipmen t or materials inc luded in a list publ ished by a Listing Organizat ion acceptable to the Authori ty Having Jurisdiction. Listings shall state ei ther tha t the equ ip m en t or materials mee t appropria te s tandards or have been tested an d found suitable for use in a specified manner : Marine Listings shall account for condi t ions of use on ships and o ther vessels. Products having Marine Listings shall have been evaluated for suitability in the mar ine env i ronmen t which may include special requi rements for vibration, shock, corrosion, temperature , acceleration, an d other relevant factors for sh ipboard use.

System Strainer. A filter or strainer a r ranged to remove foreign mat ter f rom water moving th rough piping serving more than one head. (This te rm is used in 2-3.1 but is no t defined.)

664

N F P A 750 ~ A 9 6 R O P

11-2-1.1 All materials and devices essential to successful system operat ion shall be mar ine listed.

Fine Print Note: In the ahsence of mar ine listings, the Authori ty Having Jurisdict ion may accept o ther listings or per formance criteria.

11-2-2.2.8 Mount ing systems shall be mar ine listed• 11-2-3.2.3 CPVC pipe listed for use in fire protection systems may

be used unde r the following conditions: l a l n accommoda t ion and public spaces where:

• All pipe and fittings are above a ceiling having a m i n i m u m B-15 fire resistance rat ing or art: located beh ind a m i n i m u m B-15 bulkhead.

b. No combustibles are located above the ceiling or beh ind the bulkhead except for small a m o u n t s of combust ible wiring insulation and the water mist pipe itself.

c. Penetrat ions t h rough A class decks and bulltheads shall be made with stainless s tee lspool pieces having a m i n i m u m length of 18 pipe diameters on each side of the bulkhead.

11-2-4.2.3 Screwed un ions are permit ted. 11-2-4.2.4 Bushings and o ther reducing fittings are permitted.

Restricting orifices are not permit ted. 1-2-5.5 The system shall be a t tached to the s tructure of the vessel in

a m a n n e r that accounts for forces that may be developed by: 1) the weight of the system; 2) m o v e m e n t of water and gas; 3) swaying pipe due to mot ion of the vessel; 4)

11-2-5.6 Hangers utilizing threaded fasteners shall be provided with a means for prevent ing loosening due to vibration.

11-2-7.3 Resistance against corrosion shall be achieved th rough the use of proper materials t h roughou t the full thickness of tile componen t . Coatings shall no t be used as the principle means for achieving corrosion resistasace.

11-2-8.2 The system shall be capable of cont inued operat ion without significant increase in head loss, for a period est imated to be ample when consider ing the type of protection provided, the condit ion of the water and similar circumstances. The m i n i m u m durat ion of system filtration u n d e r adverse condit ions shall be 1 hour. Exception: Small systems protect ing special hazards may have filtration ar ranged for a durat ion.

11-2-8.1 Strainers and filters shall be listed for use in water mist fire suppress ion systems.

11-2-8.7 Filters located between sea water inlets and the system shall be fitted with an emergency r edundan t filter and changeover valve. It shall be possible to replace or clean the filter without impair ing or shut t ing down supply to the system.

11-2-9.1 Pump systems shall comply with the provisions of the Internat ional Convent ion for the Safety of Life at Sea (SOLAS), Consolidated Edition, 1992, paragraphs II/2-12.5.1 t h rough II/2-12.8, inclusive. 11-2-9.2 To be de termined. 11-2-9.5 P u m p systems on vessels classified by a vessel classification

society shall be in accordance with classification society rules for vital systems.

11-2-9.6 Pumps shall no t be subject to automat ic shut down dur ing actual system operat ion.

11-2-9.7 Failure of any one p u m p shall no t impair system performance . Exception: Where fire main p u m p s can s imultaneously supply both the fire main d e m a n d and the sprinkler d e m a n d and a in terconne ction in accordance with 11-3-5.14 is provided.

11-2-9.8 Water mist pumps shall no t be located in compa r t men t subject to f looding or fire condi t ions tha t could occur s imultaneously with f looding or fire in spaces hous ing fire main p u m p s or emergency generators .

11-2-9.9 Pumps shall be capable of being started from the conu'ol station and at the p u m p unit.

11-2-10.1.2 Water mist systems shall be of the wet pipe type except: 1) Small sections of dry pipe or preaction type where piping is

subject to freezing. 2) Manual systems where acceptable to the Authori ty Having

Jurisdiction. 3) Zoned and total f looding systems protect ing special hazards

where acceptable to the Authori ty Having Jurisdiction. 11-2-10.3.10 Systems capable of manua l actuat ion protect ing

machinery spaces shall have controls located outside the machinery space.

11-2-10.3.11 M a n n e d machinery spaces shall have addit ional controls located in the m:tchinery space.

11-2-10.3.11.1 Travel distance to control shall no t exceed 75 ft. 11-2-10.3.12" Systems of the preaction, pilot operated, or zoned

f looding type protect ing public spaces shall be ar ranged such that initial actuat ion does not obscure vision in more than 45 sq. m.

A-11-2-10.3.12 Means for subsequen t actuat ion of addit ional nozzles if the fire is no t initially control led shall be tested and found to operate reliably when exposed to water mist.

11-2-10.5 All circuits and wiring shall be fall safe such tha t any single open or g r o u n d fault on may circuit or conductor shall no t cause a system impa i rmen t but will cause a t rouble signal.

Exception 1. Conductors carrying cur ren t to motors (e.g. p u m p s and compressors)

2. Conductors inside enclosures. 11-3-5.14 Connect ions with other systems. 11-3-5.14.1 Connect ions with fire mains, fire depa r tmen t

connections, shore connect ions and o ther sources of water shall be fitted with filters in accordance with 11-2-8.

11-3-5.14.2.1 The in te rconnec t valve shall be accessible without the use of ladders or tools shall no t require a force of more t han 80 N applied tangentially to the opera t ing m e c h a n i s m u n d e r full flow conditions.

11-3-5.. 14.2.2 For systems on vessels of 4 decks or greater, the fire main in te rconnec t xralve shall be capable of remote control f rom the control station.

11-3-5.14.3 In terconnects shall be provided with check x-aires to prevent flow out o f the mist system.

11-3-6 Additives. 11-3-6.1 Additives shall no t be in t roduced into water supplies

unless the additive and the system componen t s have been tested an d listed for compatibility. Listing of additives shall consider effect on drople t formation, compatibility with materials of system construction, and heal th effects.

11-3-6.2 Systems requir ing additives for proper system operat ion shall have a sufficient quanti ty of addit ion to comply with the dura t ion of system per formance given in 11-5-3.5 and Chap te r .

11-3-7 The system shall be provided with s tored water, s tored atomizing media, s tored energy and shall be a r ranged for operat ion at file design flow and pressure over the design area for a dura t ion of one minu te without external sources of power, water or gas.

11-3-7.1 There shall be no appreciable interrupt ion of system operat ion dur ing transition between power sources.

11-4-2.1 The m i n i m u m area of protection shall be 280 sq. m. Exception: Smaller design areas are permi t ted for special systems

where acceptable to the authori ty having jurisdict ion. 11-4-4.1.1.1 Each automatic source of water and pressurizing

m e d i u m may be fitted with a shut off valve. 1 1 4 5 . 2 Systems protect ing machinery spaces, deep fat fryers and

other hazards subject to sudden, intense f lammable liquid fires shall no t have a discharge t ime delay between the sensor detect ing the need for the system to actuate and the actuat ion of the system.

11-4-5.2.1 For accommodat ion and public spaces discharge t ime delays shall subject to the requ i rements of the authori ty having jurisdiction.

11-4-6.2 Each section of the system shall be fitted with a test line capable of d ischarging the m a x i m u m design flow for the section. The test connect ion shall be piped to a drain or overboard such tha t the full flow can be susta ined for 1 minu te without water damage.

11-4-7 Air t rapped in system piping and capable of degrading system per formance shall be automatically expelled via devices specifically for that purpose.

11-4-8 Shore Connect ions . 11-4-8.1 Each system serving more than one space shall be fitted

with a shore connect ion. A single connect ion may serve mult iple systems. Vessels greater t han 100 feet in length overall shall be fitted with a shore connec t ion at a principle gangway on each side of the vessel. Each shore connect ion shall be clearly marked to show the purpose of the connect ion and. req~uired pressure and. flow:

11-4-8.2 Each shore connect ion shall have a 2-1/2 mcb diameter female swivel wye fitting having National Standard hose threads in accordance with NFPA 19XX.

1 1 4 8 . 3 Vessels on internat ional voyages shall have an internat ional shore connect ion in addit ion to the requi rements 1148.2 .

11-7-4.1 Gas and water storage cylinders shall be protected f rom direct exposure to weather.

11-7-4.2 Spaces hous ing gas cylinders shall be provided with natural or forced ventilation.

11-7-4.3" Rooms hous ing gas cylinders filled with any gas o ther than compressed air shall be fitted with a door that swings in the direction of egress and doors shall latch in the full open position.

A-11-7-4.3 Personnel have been killed servicing gaseous fire ext inguishing systems when accidental discharges allowed gas to fill the space hous ing the storage cylinders.

11-7-3.1.1 The supply of iner t gas shall be 120% of the design volume given in 7-3.1.

Exception: Where an automat ic means is provided to indicate leakage of gas f rom the storage cylinder.

11-7-4.1 For vessels exceeding 100 feet in length overall, systems serving mach inery spaces shall be capable of supplying water at the m a x i m u m design flow for a durat ion no t less than 6 hours.

665

N F P A 750 - - A 9 6 R O P

11-8-5 There shall developed and submit ted for review, a set of clearly unders tandab le rules for the spacing of nozzles. These rules slmll address: spacing rationale, locations o f nozzles relative to obstructions, decks, bulkheads, and forced ventilation points; flow requirements; and heat responsive e lement response times.

11-9-2.1.3 The system shall be c leaned and tested in accordance with: (to be developed: s tandard for cleaning industrial hydraulic systems.)

Exception: system where the smallest orifice or port is no t smaller than 1 /8 inch.

11-10-1.1 The responsibility for properly main ta in ing a water mist fire suppress ion system shall be the obligation of the vessel owner. A periodic inspection, testing and ma in tenance program shall be used to show the system is in good opera t ing condit ion and tha t defects and impai rments are identified and prompt ly corrected.

11-10-5 Records: A water mist system inspection, testing, and ma in tenance log book shall be kept with the vessel 's mach inery system log book. The book shall identify the t ime, date, na ture and ship 's officer responsible or any inspection, test, impai rment , and ma in t enance of the water mist fire suppress ion system. SUBSTANTIATION: New chapter for mar ine installations. COMMITrEE ACTION: Accept in Principle. COMMITrEE STATEMENT: The Technical Commit tee has decided to go forward with this chapter at this time. In the in ter im a Task Group will he f o rmed to develop additional commen t s on this chapter. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF NEGATIVE: DINENNO: 1. Some of the requ i rements given are in conflict with

the governing IMO regu l a t i ons .T h i s section has the effect of making fu l lyIMO compliant systems unacceptable unde r NFPA 750.

2. Some of the requi rements specify IMO specific language (e.g., B-15 bulkbead, etc.)-which are undef ined .

3. Some of the requi rements deserve more careful s tudy particularly with res~pect to their impact on mar ine applications.

4. Some of the requi rements m a y b e in conflict with other relevant NFPA standards.

5. The requi rements for gas cylinders (Section 11-7.4.1.3) appear excessive particularly if the-gas is air or the space volume large with respect to the gas volume.

6 .-In general , the section specifies in detail mayaspec t s of system design Which exceed the requ i rements of NFPA 750 for o ther applications. This is no t a problem in principle, bu t the justif ication of such concept of a specific section on mar ine applications, I cannot suppoi-t the draft in its cur ren t form. EXPLANATION OF ABSTENTION:


(Log #94) 750- 96 - (A-7-2.1): Reject SUBMITTER: Pierre Girard, Securiplex Inc. RECOMMENDATION: T he one hour fire ra ted enclosure should be removed or should be left to the discretion of the Authori ty Having Jurisdict ion or the customer. SUBSTANTIATION: Most of the customers will have their water mist system, without an enclosure on a skid base, and sitting a long a wall. This does no t differ f rom a sprinkler sys tem riser where are located the control valves and the alarm valves. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The Appendix material is no t mandatory. It could be provided at the request of the anthori ty having jur isdic t ion or the customer. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:



(Log #CP1) 750- 97 - (Entire Document ) : Accept SUBMITrER: Technical Commit tee on Water Mist Fire

r ession Systems MMENDATION: Provide a new document , NFPA 750 to

address the design, installation, and use of water mist systems as shown at the end of dais report. SUBSTANTIATION: Water mist fire protect ion systems are considered to be a viable system for select fire protection a oplications. The systems have been used for some t ime in the ~u ropean community , primarily in the mari t ime envi ronment .

666

Application env i ronments for mist technology have m u c h potential, however, a l imited a m o u n t of design specific informat ion is known at this time. The known pieces of informat ion have been incorporated into the document .

As you review the Commit tee Proposal for this standard, you will note that it contains a n u m b e r of e lements which are comparable to o ther types of fire suppress ion systems including sprinkler systems, CO 2 systems and halon systems. In many ways, water mist is a hybrid of these systems. While it utilizes water as the suppress ion mechanism, it delivers it in a non-tradit ional way.

Water mist ext inguishing or control characteristics are directly related to the distribution and dispersion of fire spray water drops to the protected envi ronment . Wate r supplies, p iping and distribu-tion networks and drop genera t ion me thods mus t all be closely regulated and coordinated to acbieve an op t imum mist. The purpose of this s tandard is to provide a reliable system to accomplish this goal. A summary of the contents of each chapter follows-

Chapter I General Information This chapter provides the basic definit ions and descriptions which

are essential to unde r s t and ing water mist technology. The un ique definit ions for water mist include descript ions of i tems such as a tomizing media, total compa r tmen t application systems, Dvf, local application systems, twin fluid systems, water mist, water mist systems and zone applicat ion systems.

A basic r equ i r emen t of what qualifies as water mist required the deve lopment of a series of definitions. These definitions, and the addit ional classifications of mist types are necessary to dist inguish these systems f rom sprinkler systems (as governed by NFPA 13, S tandard for the Installation of Sprinkler Systems) an d f rom water spray systems (as governed by NFPA 15, Standard for Water Spray Fixed Systems for Fire Protection). The "water mist" definit ion stipulates that 99 pe rcen t of the genera ted droplets in a cumulative vo lume have a d iameter less than 1,000 microns (1 ram). This distinction is provided to identify water mist as being different f rom other water based systems.

"Application" definit ions (local, total c o m p a r t m e n t and zone) establish a basis for how or why the system may be installed - to protect a specific piece of equipment , an entire c o m p a r t m e n t or a port ion of a compar tment .

Section 1-5 provides a n u m b e r of uses, goals mad limitations for water mist. System designers mus t be acutely aware of the type of fuel package and the in~ended purpose of the system.

Sections I-6 and 1-7 discuss some related factors which should be considered.

Chapter 2 System Components and Hardware The hardware specifications a n d requ i rements for the system

componen t s are discussed in this chapter. Critical componen t s which are crucial to system reliability and per formance are required to be listed.

System gas or water containers are in t ended to satisfy the criteria for pressure vessels. Specific criteria has been provided for the marking, suppor t and envi ronmenta l control of such containers.

Sections 2-3 and 2-4 govern piping materials. The low pressure systems, in general , are allowed to utilize materials with pressure ratings which are comparable to sprinkler systems. Intermediate and h igh pressure systems mus t utilize piping materials which are in conformance with ANSI B31.1, Power Piping Code.

Section 2-6 provides informat ion on the per formance an d discharge characteristics of the nozzle. Due to the variations associated with the different mist genera t ion techniques , a set of uni form evaluation criteria for all nozzles has been established. These i tems are in tended to be utilized by the listing agencies where testing water mist nozzles.

Section 2-8 (also see Chapter 7) provides specific criteria for system strainers and filters. Water mist systems will typically use small d iameter pipe and nozzles, with very small orifice openings, thus quality control of water supplies is critical.

Section 2-9 has been included to describe the requ i rements for pumps . NFPA 20, S tandard for the Installation of Centrifugal Fire Pumps does not currently govern p u m p s other than centrifugal types. Pumps used in water mist configurat ions are typically low flow, positive d isp lacement types which are outside the present requi rements of NFPA 20.

Section 2-10 (also see Section 4-9) provides requi rements for the operational aspects of the system. This included detect ion systems, actuat ion methods (automatic and manua l ) and control of the system. The detect ion and a larm requ i rements are in tended to comply with NFPA 72, National Fire Alarm Code (or C A N / U L C $524-M-86 and $529-M-87).

Chapter B System Description This cbapter describes the various operational aspects an d means

for water mist systems. Section 3-2 discusses the level of system protect ion in tended for different objectives. Local application systems are typically considered for protect ion of specific objects or

N F P A 7 5 0 - - A 9 6 R O P

equipment . Total c o m p a r t m e n t systems are typically considered for protect ion of an entire space, vo lume or enclosure. Zoned systems describe a derivative of a c o m p a r t m e n t system a n d are in t ended to result in operat ion of a g roup ing (but no t all) of systems in a relatively large compar tment .

Section 3-3 describes nozzles as be ing automatic , non-automat ic or hybrid types. Automat ic nozzles are individually activated. Non- automatic nozzles contain open orifices and discharge simultaneously.

Section 3-4 provides a descript ion of the two basic water mist genera t ion me thods - single fluid and twin fluid. Single fluid systems are des igned to use water only and genera te mist t h rough high velocity discbarge of water into the air, discharge of water onto a mechanical surface, discharge of two water s t reams into one another , mechanical or electrically induced vibration or thermal heal ing of water above its boil ing point in a closed container followed by discharge.

Twin fluid systems use a dual fluid approach to genera te the mist. The water is directed into the mist nozzle with o n e p i p i n g system while a second piping system delivers the a tomizing fluid (media) . Atomizing media is typically composed of high pressure air or ni trogen. The atomizing media acts to impact a shear force on the water and create the mist drops.

Chapter 4 Installation Requi rements This chapter establishes the criteria for use of the system

componen t s which are discussed in Chapter 2. It also supp lements some of the informat ion ~i thin Chapter 3 for operational features associated with the various systems.

Section 4-2 describes specific criteria for the positioning, location, use and spacing of nozzles. It is no ted that much of this criteria falls to the listing requirements; of these systems.

Section 4-3 governs the use a nd installation of piping systems including pressure ratings, compatibility and support .

Section 4-5 specifies a n u m b e r of r equ i rements for storage cylinders. While some of this criteria will eventually be within the purview of the product s tandard for listing, specific criteria has been given for p roper installation and use of both h igh pressure and low pressure cylinders.

Section 4-6 is a compan ion section to Section 2-9.3 with regard to the operator and installation of pumps . T he power supply for the p u m p is in t ended to comply with NFPA 20. T he other installation provisions will stay within the confines of NFPA 750.

Section 4-8 provides a series of requi rements for various types of water supply, atomizing media, activation and pressure regulat ing valves. This section provides requi rements for automat ic operat ion of tllese devices (,as part of a normal system opera t ing feature) as well as for manua l operat ion of these devices.

Section 4-9 describes the appropria te installation me thods and requi rements for the operational componen t s - control units, wiring methods, detect ion methods , and manual operat ing methods. . In order to achieve this, reference to various directly applicable documen t s is given.

Chapter fi Design Objectives and Hazard Classifications As stated in the first paragrapb of this chapter, no specific design

criteria for water mist fire protection systems exists at dais point in time. This will likely result in most systems being installed as pre- eng ineered systems early on. Chapter 5 provides an in dep th process for design parameters associated with water mist.

Section 5-2 details t he parameters which will impact the system selection type, design and chal lenge to the systems' ability to control or suppress the fire as desired. Performance of the system is affected b y t h e d imens ions of the compar tment , area or object being protected; mechanical or natural ventilation which may impact the t ransport of the mist particles and the fuel package or fiiel type which is present.

Section 5-2 is in tended to give per formance criteria and specification criteria for system operat ion as well as for selected, individual components . An extensive list of items to be evaluated has been included in an appendix section for 5-3.

Chapter 6 Calculations The fluid calculations for water and atomizing media are detailed

in this chapter. Section 6-2 requires the use of the Darcy-Weisbach Calculation Metbod for Intermediate and High Pressure Systems. Pressure drop values will thus be derived by use of the Moody diagram, pipe roughness ~alues and the Reynolds Number . Section 6-3 will permi t the use of the Hazen-Williams equat ion for low pressure systems.

Section 6-4 has no t been completed, it is in tended to provide the procedure for balancing the atomizing media and the water supply at the nozzle on tuna fluid media systems. This p rocedure is critical to insure tha t p roper mixing occurs to genera te the appropria te drop size distribution.

Chapter 7 Water Supplies and Atomizing Media A n u m b e r of s t r ingent controls are imposed on the water supply

source and the atomizing media source. Sections 7-3 and 7-5 describe the vo lume of each fluid which mus t

be maintained. This volume is a funct ion of system discharge durat ion.

Section 7-6.1 governs quality control issues for supply sources. Due to the very small orifice sizes associated with water mist nozzles, a range of measures including use of de-mineral ized water and installation of filters and strainers is required in some cases. These i tems are considered to be necessary to avoid blockage of the nozzles.

Section 7-6.2 provides requi rements used for water mist pumps . These p u m p s may not always be centrifugal pumps thus they are outside the cur ren t scope of NFPA 20, S tandard for the Installation of Centrifugal Fire Pumps. Pump criteria is then appropriate to cover this s tandard.

Sections 7-6.3 t h rough 7-6.5 covers the use of tanks, storage containers, and fire d e p a r t m e n t connect ions. There are a n u m b e r of exceptions to the fire d e p a r t m e n t connect ion provision which would make such connect ions impractical.

Section 7-7 provides criteria to enhance the reliability of the a tomizing media including the source, pressure condit ion and a r r a n g e m e n t of the a tomizing media.

Chapter 8 Plans and Documentation This chapter provides a list of i tems to be inc luded on the working

plans when submi t ted for approval by the authori ty having jurisdiction.

Sections 8-2 and 8-3 detail the necessary requi rements for complet ing the fluid calculations for water and atomizing med ia (if applicable).

Since some mist systems require an interface with some type of electrical control system, a r equ i r emen t for submiss ion of an as-built installation drawing, including operat ion sequence , is required by Section 8-4. The as-built criteria extends to all port ions of the system controls including automat ic and manua l operational means.

Chapter 9 System Acceptance Various functional, operational and quality tests are required by

this chapter. As with all o ther fire protection systems, some type of funct ional test is required to insure tha t the system performs as intended.

Section 9-2 specifies what i tems are to be tested, how they are tested and how the results should be considered. Section 9-2.6 requires an operational test with water where this is a practical option.

Chapter l0 System Maintenance Since this technology is relatively new, the requi rements of NFPA

25, S tandard for the Inspection, Testing, and Maintenance of Water- Based Fire Protection Systems are, for the most part, no t practical to apply to water mist systems. Specific activity items for inspection, testing and ma in tenance of water mist systems are specified a long with a required frequency. Due to the un ique nature associated with many of tlae system components , many procedures are to be in accordance with the requ i rements of the manufacturer . C O M M I T r E E ACTION: Accept. NUMBER OF COMMITrEE MEMBERS ELIGIBLE TO VOTE: 30 VOTE ON COMMITTEE ACTION:


EXPLANATION OF NEGATIVE: CHARNEY: Paragraph 4-5.3: This paragraph arbitrarily limits the

location of containers. Other NFPA standards allow the location of agent containers within the hazard. NFPA 2001, paragraph 2-1.3.2 reads "Storage containers shall be located as close as possible to or within the hazards they protect." The addit ional append ix material in 2001, A-2-1.3.2 states "Storage containers shou ld not be exposed to a fire in a m a n n e r likely to impair performance."

This paragraph should be rewritten to conform with NFPA 2001. EXPLANATION OF ABSTENTION:

GIOSEFFI: See my Explanat ion of Abstention on 750-1 (Log #4).

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N F P A 7 5 0 m A 9 6 R O P

NFPA 750

Standard for the

Installation o f Water Mist Fire Protection Systems

1996 Editio n

NOTICE: An asterisk (*) following the n u m b e r or letter des ignat ing a paragraph indicates explanatory material o n that paragraph in Appendix A.

Informat ion on referenced publications can be f o u n d in Chapter 11 and Appendix C

Chapter 1 General Information

1-1" Scope. This s tandard contains the m i n i m u m requi rements for the design, installation, ma in tenance and testing of f ixed water mist systems.

1-2 Purpose. The purpose o f this s tandard is to provide a reasonable degree of protection for life and property f rom fire t h rough the standardizat ion of design, installation, main tenance , and testing requi rements for water-based fire suppress ion systems that use a specific spray (mist) that absorbs heat, displaces oxygen, or blocks radiant hea t to control, suppress, or ext inguish fires as requi red by the application. This s t andard endeavors to establish m i n i m u m requi rements for water mist technology based on sound eng ineer ing principles, test data, and field experience. Noth ing in this s tandard is i n t ended to restrict new technologies or al ternate a r rangements , provided the level of safety prescr ibed by this s tandard is no t lowered. Materials or devices no t specifically des ignated by dais s tandard shall be utilized in accordance with all conditions, requi rements , and limitations of their listings.

NOTE 1: Water mist systems are specialized fire protect ion systems. Design and installation of these systems necessitates specialized training, knowledge, and experience.

NOTE 2: Water mist systems offer potent ia l benefits for many specialized applications, particularly where available water supplies are l imited or where the application of water needs to be restricted. Potential benefits also migh t exist for applications previously protected by gaseous and o ther fire suppressan t agents.

1-3 Retroactivity Clause. T he provisions of this d o c u m e n t are considered necessary to provide a reasonable level of protect ion f rom loss of life and proper ty f rom fire. They reflect si tuations and the state of the art at the t ime the s tandard was issued.

Unless otherwise noted, it is no t in t ended that the provisions of this d o c u m e n t be applied to facilities, equ ipment , structures, or installa- t ions that were existing or approved for construct ion or installation prior to the effective date of this documen t .

Exception: In those cases where it is determined by the authority having jurisdiction that the existing situation involves a distinct hazard to life or property, this standard shall app,.

1-4 Def'mitions and Units.

1-4.1 Definitions.

Approved.* Acceptable to the authori ty having jurisdict ion.

Atomizing Media. Compressed air or o ther gases tha t produce water mist by mechanical mixing with water.

Authority Having Jurisdiction. T he organization, office, or individual responsible for approving equ ipment , an installation, or a procedure.

Deluge System. A water mist system us ing open nozzles a t tached to a piping system connec ted to a water supply th rough a valve tha t is opened by means of a detect ion system installed in the same area as the mist nozzles. W h e n the valve opens, water flows into the piping system and discharges t h rough all nozzles a t tached to the system.

Dry Pipe System. A water mist system us ing automat ic nozzles a t tached to a piping system conta in ing air or n i t rogen unde r pressure, the release of which (as f rom an open ing of an automatic

nozzle) allows the water pressure to open a dry pipe valve. The water then flows into tile piping system and out t h rough any open nozzles.

Dvf. A drop d iameter such that the cumulative volume, f rom zero diameter to this respective diameter, is the fraction, f, of the cor responding sum of the total distribution.

NOTE: Dv 0 50 is tile volume median diameter; that is, 50 percent of ~e- to ta l volume of liquid is in drops of smaller d iameter and 50 percent is in drops of larger diameter.

Enclosure. The case, housing, partition, or walls that will substantially contain water mist in the vicinity of the hazard for a sufficient length of t ime to achieve the fire protect ion objectives.

Engineered Systems. Those systems that need individual calculation and design to de te rmine the flow rates, nozzle pressures, pipe size, area or vo lume protected by each nozzle, discharge density of water mist, the n u m b e r and types of nozzles, and the nozzle p lacement in a specific system.

Fire Control. The limitation of the growth of a fire by prewetting adjacent combust ibles and controll ing ceiling gas tempera tures to prevent structural damage.

Fire Ext inguishment . The complete suppress ion of a fire until there are no bu rn ing combustibles.

Fire Suppress ion. The sharp reduct ion of the rate of heat release of a fire and the prevent ion of regrowth.

High Pressure System. A water mist system where the distr ibution system piping is exposed to pressures of 500 psi (34.5 bars) or greater.

Intermediate Pressure System. A water mist system wbere the distr ibution system piping is exposed to pressures greater than 175 psi (12.1 bars) but less than 500 psi (34.5 bars).

Listed.* Equ ipmen t or materials included in a list publ ished by an organization acceptable to the anthori ty having jur isdict ion and conce rned with product evaluation that mainta ins periodic inspection of product ion of listed equ ipmen t or materials mad whose listing states ei ther that the e q u i p m e n t or material meets appropriate s tandards or has been tested and f o u n d suitable for use in a specified manner .

Local Application System. A water mist system ar ranged to discharge directly on an object or hazard in an enclosed, unenclosed, or open outdoor condition.

Low Pressure System. A water mist system where the distribution piping is exposed to pressures of 175 psi (12.1 bars) or less.

Preaction System. A water mist system using open nozzles a t tached to a piping system conta in ing air tha t migh t or migh t not be u n d e r pressure, with a supplementa l detect ion system installed in the same areas as the mist nozzles. The actuat ion of the detect ion system opens a valve that allows water to flow into the piping system an d discharges th rough all o p e n e d nozzles in the system.

Pre-Englneered Systems. Those systems having p rede te rmined flow rates, nozzle pressures, and volumes a n d spray flux densities of water mist. These systems have the specific pipe size, m a x i m u m an d m i n i m u m pipe lengths, flexible hose specifications, n u m b e r of fittings, and n u m b e r and types of nozzles prescr ibed by a testing laboratory. Systems are provided with either a serf-contained or external water supply. The hazards protec ted by these systems are specifically l imited as to type a n d size by a testing laboratory, based on actual test fires. Limitat ions on hazards tha t are allowed to be protected by these systems are conta ined in the manufac tu re r ' s installation manual , which is re fe renced as part of the listing.

Shall. Indicates a manda to ry requi rement .

Should. Indicates a r ecommenda t ion or tha t which is advised but no t required.

Total C o m p a r t m e n t Application System. A system designed to discharge water mist to protect all hazards in an enclosure.

Twin Fluid System. A water mist system in which water an d atomizing media are separately suppl ied to and mixed at the water mist nozzle.

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N F P A 750 ~ A 9 6 R O P

Valves.

Automatic (Activation) Valve T he valve controll ing Water flow into the mist system, including the alarm, dry pipe, deluge, zone, and g roup valves.

Control Valw Any automat ic or manual ly operated valve that controls the flow of water or air to any part of the system in the air or Water supply. This includes gate and ball valves.

Ventilation-limited. An enclosure in which, u n d e r normal operat ing conditions, all doors, hatches, and service openings in the enclosure are closed and in which activation of the water mist system automatically stops the ventilation system supplying or exhaust ing

• air f rom the enclosure.

Water Mist.* A water spray for which the Dv 0 9q, as measu red at the coarsest par t o f the spray in a plane 3.3 ft (1 rh~ t 'rom the nozzle, at its m i n i m u m design opera t ing pressure, is less than 1000 microns.

Class 1 M/st. A water mist for which 90 percent of the volume of the spray is conta ined in drops with d iameters less than 200 microns (Dv0.90<200).

Class 2 M/st. A water mist, tha t is no t a Class 1 mist, for which 90 percent of the vo lume of the spray is conta ined in drops with diameters less than 400 microns (Dr0.90<400).

Class 3 Mis~ A water mist that is no t a Class 1 or a Class 2 mist.

Water Mist Nozzle. A spec ia lpurpose device conta in ing one or more orifices des igned to p roduce and deliver water mist.

Water Mist System, A distribution system connec ted to a water supply and equ ipped with one or more nozzles capable of delivering wa-ter mist i n t ended to control, suppress, or ext inguish fires and tha-t has been demons t r a t ed to meet the pe r fo rmance requi rements of its listing and dais standard.

Wet Pipe System. A water mist system us ing automatic nozzles a t tached to a piping system conta in ing water and connec ted to a water supply s-o tha t water discharges immediately f rom nozzles ope ra t edby the heat f rom a fire. -

Zone Application System. A system desigaaed to protect hazards in a p rede te rmined port ion of an enclosure.

1-4.2 Units.

1-4.2.1 Metric units of m e a s u r e m e n t in dais s tandard are in accordance with the modern ized metr ic system known as the International System of Units (SI). Liter and bar units are outside o f but recognized by SI anti are commonly used in international fire protection. These units are provided with their conversion factors in Table 1-4.2.9.

1-4.2.2 I f a v a l u e for a m e a s u r e m e n t provided in this s tandard is followed by an equivalent value in o ther units, the first stated value shall be regarded as the requirement . A given equivalent value shall be considered an approximate value.

Table 1-4.2.2

1-5" General.

1-5.1 A Water mist system is a fire protect ion system using very fine water sprays (i.e., water mist). The very small water droplets allow the water mist to control or ext inguish fires by cooling of the f lame and fire plume; oxygen d isp lacement by water vapor; and radiant hea t a t tenuat ion.

1-5.2 Use and Limitations.

1-5.2.1 Water mist systems are used for a wide range of per formance objectives, including the following:

(a) Fire ext inguishment ;

(b) Fire suppression;

(c) Fire control;

(d) Tempera tu re control.

(e) Exposure protection.

1-5.2.2" Water mist systems shall no t be used for direct application to materials that react with water to produce violent reactions or significant amoun t s of hazardous products. These materials include:

(a) Reactive metals, such as l i thium, sodium, potassium, magne- sium, t i tanium, zirconium, u r a n i u m and p lu tonium.

(b) Metal alkoxides, such as sod ium methoxide .

(c) Metal amides, such as sod ium amide.

(d) Carbides, such as calcium carbide.

(e) Halides, such as benzoyl chloride and a l u m i n u m chloride.

(f) Hydrides, such as l i thium a l u m i n u m hydride.

(g) Oxyhalides, such as phosphorus oxybromide.

(h) Silanes, such as trichloromethylsilane.

(i) Sulfides, such as phosphorus pentasuifide.

(j) Cyanates, such as methylisocyanate.

1-5.2.3 Water mist systems shall no t be used for direct application to liquefied gases at cryogenic tempera tures (such as liquefied natural gas), which boil violently when heated by water.

1-6 Safety.

1-6.1" Hazards to Personnel. For fire situations, suitable safeguards shall be provided to ensure p rompt evacuation of and to prevent entry into hazardous a tmospheres and also to provide means for p romp t rescue of a n y t r a p p e d personnel . Safety i tems such as

Metric Conversion Factors

Name of Unit Unit Symbol Conversion Factor

Millimeter m m 1 in. = 25.4 m m Square meter m 2 1 ft 2 = 0.0929 m 2 Liter L 1 gal = 3.785 L Cubic decimeter d m 3 1 g~_ = 3.785 d m 3 Cubic mete r m 3 1 ft 3 = 0.028317 m $ Kilogram kg 1 lb = 0.4536 kg Kilograms per cubic meter k g / m 3 1 Ib/f t 3 = 16.0183 k g / m 3 P:~cal Pa 1 psi = 6895 Pa Bar bar 1 psi = 0.0689 bars Bar bar 1 bar = 105 Pa Liter per minu te per square meter L / m i n / m 2 1 g p m = 40.746 L / m i n / m 2 Micron [t 1 m m = 1000~t ~1000 microns /

N O T E 1 : F o r a d d i t i o n a l c o n v e r s i o n s a n d i n f o r m a t i o n , s ee A S T M E380, Standard Practice for Use of the International System of Units (SI) (the Modernized Metric System ). N O T E 2: I n C a n a d a , r e f e r to C S A C AN3-A234 .1 , Canadian Metric Practice Guide. N O T E 3: T h e a b b r e v i a t i o n "gal" i n d i c a t e s t h e U.S. g a l l o n m e a s u r e .

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N F P A 7 5 0 - - A 9 6 R O P

~ ersonnel training, warning signs, discharge alarms, self-contained reathing apparatus, evacuation plans, and fire drills shall be

considered.

1-6.2 Electrical Clearances.

NOTE: As used in this standard, "clearance" is the air distance between water mist system equipment , including piping and nozzles, and unenc losed or un insu la ted live electrical components at o ther than g round potential. The m i n i m u m clearances provided are for the purpose of electrical clearance unde r normal conditions; they are no t in t ended for use as "safe" distances dur ing water mist system operation.

1-6.2.1 All system componen t s shall be located to mainta in no less than m i n i m u m clearances f rom energized electrical parts. The following references shall be considered as the m i n i m u m electrical clearance requ i rements for the installation of water mist systems:

(a) ANSI G-2, NationalElectricalSafety Code,,

(b) NFPA 70, NationalElectrical Co&<R);

(c) Title 29, Code of Federal Regulations, Part 1910, Subpart S.

1-6.2.2 Where the design basic insulation level (BIL) is no t available and where nominal voltage is used for the design criteria, the highest m i n i m u m clearance specified for this g roup shall be used.

1-6.2.3 The selected clearance to g r o u n d shall satisfy the greater of the switching surges of BIL duty, rather than being based on nomina l voltage.

1-6.2.4 The clearance between un insu la ted energized parts of the electrical system e q u i p m e n t and any port ion of the water mist system shall no t be less than the m i n i m u m clearance provided elsewhere for electrical system insulation on any individual componen t .

1-7 Environmental Factors. W h e n selecting water mist to protect a hazard area, the effects of water runof f on the env i ronmen t shall be considered. Particular a t tent ion shall be given to any water additives or any chemicals that can be carried out of the hazard area by the water.

Chapter 2 System Components and Hardware

2-1 General. This chapter provides requi rements for the correct use of water mist system components .

2-1.1 All componen t s shall be listed for their in tended use.

Exception No. 1: Where approval o f system components is specifically permitted to be substituted for listing.

Exception No. 2: Where components are part o f a listed, pre-engineered system.

2-1.2 System componen t s shall be rated for the m a x i m u m working

~ ressure to which they are exposed but not less than 175 psi (12.1 ars).

2-2 Gas and Water Containers.

2-2.1 Capacity. Gas and water containers, if provided, shall be sized to supply quanti t ies of gas and water as required by Chapter 7.

2-2.2 Design.

2-2.2.1" Gas and water containers shall be des igned for secure installation according to the manufac tu re r ' s installation manual . Installation design also shall provide for convenient individual servicing or con ten t measur ing.

2-2.2.2* Gas and water containers shall be des igned to mee t the requi rements of the US. Depa r tmen t of Transpor ta t ion or of Transpor t Canada, if used as sh ipp ing containers. If no t sh ipp ing containers, they shall be designed, fabricated, inspected, certified, and s tamped in accordance with Section VIII of the ASME Boiler and Pressure Vessel Code. The design pressure shall be suitable for the m a x i m u m pressure developed by the water mist system at 130°F (54°C).

2-2.2.3 Each water container shall have a p e r m a n e n t namepla te or o ther p e r m a n e n t mark ing specifying the liquid he ld in the container ( including additives) and the nominal water volume and pressurization level (where applicable) of the container.

670

Exception: Marking shall not be required on each water container i f the information is provided on a nameplate or placard permanent!y installed on the system at a location convenient for servicing or content measuring.

2-2.2.4 External s ight glasses on water containers shall be protected against mechan i ca ldamage .

2-2.2.5 Each gas container shall have a p e r m a n e n t namepla te or o ther p e r m a n e n t markinlJ specifying the type of gas, weight of gas, weight of container, nomina l gas volume, and pressurization level of the container.

Exception: Marking shall not be requ_ ired on each gas container i f the information is provided on a nameplate or placardpermanentty installed on the system at a location convenient for servicing or content measuring.

2-2.2.6 A reliable means shall be provided to indicate the pressure in refillable pressurized gas contmners.

2-2.2.7 Storage tempera tures shall be main ta ined within the range specified in the manufac tu re r ' s installation manual . External t ieating or cooling shall be an acceptable m e t h o d to keep the t empera tu re of the storage container widfin desi red ranges.

2-2.2.8 Containers shall be enclosed in manufacturer- l is ted supports to prevent conta iner m o v e m e n t a n d possible physical damage.

2-2.3 Multiple Container Systems. All containers supplying the same manifold outlet shall be in terchangeable and o f the same size and charge.

2-3 Piping and Tube.

2-3.1" All piping f rom the system strainer to the nozzle shall have corrosion r'es'ista-nce at least equivalent to piping specified in Table 2- 3.2.1, Wherever the word "pipe" is used, it shall 'be unders tood also to mean "tube."

2-3.2 Low Pressure Systems.

2-3.2.1 Pipe or tube used in low pressure water mist systems shall mee t or exceed one of the s tandards in Table 2-3.2.1 or shall be in accordance with 2-3.2.3. The chemical properties, physical properties, and d imens ions of the materials given in Table 2-3.2.1 shall conform at a m i n i m u m to the s tandards cited in the table. Pipe and tube used in water mist systems shall be des igned to withstand a working pressure of no t less than 175 psi (12.1 bars). Wherever the word "pipe" is used, it shall be unde r s tood also to m e a n "tube."

Table 2-3.2.1 Pipe or Tube Stamdards

Materials and Dimensions Standard

Copper Tube (Drawn, Seamless)

Spec. for Solder Metal [95-5 (Tin-Antimony-Grade 95TA))

Spec. for Seamless Copper Tube 1

1 Spec. for Seamless Copper Water Tube

Spec. for General Requn,ements for Wrought Seamless Copper and Copper-Alloy Tube

Spec. for Liquid and Paste Fluxe.~ for Soldering Applications of Copper and Copper Alloy Tube

Spec. for Filler Metals for Brazing and Braze Welding (Classification BCuP-3 or BCuP-4)

Stainless Steel

Spec. for Seamless and Welded Austenitic Stainless Steel Tubing for General Service

Spec. for Seamless and Welded Austenitic Stainless Steel Tubing (Small-Diameter) for General Service

S~TTub c. for Welded, Unannealed Austenitic Stainless Steel ular Products

Spec. for Seamless and Welded Ferritic/Austenitic Stainless Steel Tubing for General Service

ASTM B32

ASTM 1775

ASTM B88

ASTM B25 l

ASTM B813

AWS A5.8

ASTM A269

ASTM A632

ASTM A778/A778M

ASTM A789/A789M

1Denotes pipe or tube suitable for bending ( see 2-3.5 ) according to ASTM standards.

N F P A 750 - - A 9 6 R O P

2-3.2.2 Copper tube as specified in the s tandards referenced in Table 2-3.2.1 shall have a wall thickness of Type K, L, or M where used in water mist systems.

2-3.2.3 Othe r types of pipe or tube investigated for suitability in water mist system installations and listed for this service shall be permit ted where installed in accordance with their listing limitations, including installation instructions. Bending of the pipe shall be permi t ted as provided by the listing. Pipe or tube shall no t be listed for port ions of an occupancy classification.

2-3.3 Intermediate and High Pressure Systems.

2-3.3.1 Pipe or tube shall be of noncombust ib le material having physical and chemical characteristics such that its deter iorat ion unde r stress can be predicted with reliability. Where pipe or tube is installed in severely corrosive a tmospheres , special corrosive-resistant materials or coatings shall be used. The piping shall be in accordance with ANSI B31.1, Power Piping. The internal pressure used for calculation of pipe wall thickness shall be the m a x i m u m operat ing pressure of the water mist systems at a pipe tempera tu re of 130°F (54°C).

2-3.3.2* Flexible piping, tubing, or hoses ( including connect ions) shall be listed for their i n t ended use.

2-3.4 Pipe or Tube Identification.

2-3.4.1 All pipe or tube, inc luding specially listed pipe or tube, shall be marked cont inuously a long its length by the manufac tu re r in such a way as to identify the type of pipe or tube properly. This identification shall include the manufac tu re r ' s name, model designation, or schedule.

2-3.4.2 Pipe or tube mark ing shall no t be painted, concealed, or removed prior to approval by the authori ty having jurisdiction.

2-3.5 Pipe or Tube Bending. Bending of Type K a n d Type L copper tube shall be permi t ted where bends are made with no kinks, ripples, distortions, reduct ions in diameter , or any noticeable deviations f rom a r o u n d shape. T he m i n i m u m radius of a bend shall be six pipe diameters for pipe sizes of 2 in. (51 mm) and smaller and five pipe diameters for pipe sizes larger than 2 in. (51 mm) .

2-4 Fittings.

2-4.1" All fittings used on piping described in 2-3.1 shall have a corrosion resistance at least equivalent to wrought copper fittings conforming to ANSI B16.22, Wrought copper and copper Alloy Solder Joint Pressure Fittings.

2-4.2 Low Pressure Systems.

2-4.2.1 Fittings used in water mist systems shall mee t or exceed the s tandards in Table 2-4.2.1 or shall be in accordance with 2-4.2.2.

Table 2-4.2.1 Fitting Standards

Materials and Dimensions Standard

Copper

Cast Copper Alloy Solder Joint Pressure Fittings

Wrought Copper and Copper Alloy Solder Joint Pressure ~ittings

Stainless Steel

Spec. for Castings, A usteniti G A ustenitic-Ferritic ~Duplex), for Pressure-Containing Pa*ts

Spec. for Wrought A ustenitic Stainless Steel Piping Fittings

Spec. for As-Welded Wrought A ustenitic Stainless Steel Fittings for General Corrostve Service at Low and Moderate Temperatures

Spec. for Wrought Ferritic, Fen"itic/A ustenitic, and Martensitic Stainless Steel Piping Fittings

ANSI B16.18

ANSI B16.22

ASTM A351/A351M

ASTM A403/A403M

ASTM A774/A774M

ASTM A815/A815M

671

2-4.2.2* Other types of fittings investigated for suitability in water mist installations and listed for this service shall be permi t ted where installed in accordance with their listing limitations, inc luding installation instructions.

2-4.2.3 Screwed un ions shall no t be used on pipe larger than 2 in. (51 mm) . Couplings and un ions of o ther than the screwed type shall be listed for the in tended use.

2-4.2.4 A one-piece reducing fitt ing shall be used wherever a change is made in the size of pipe.

Exception: Hexagonal or face bushings shall be permitted in reducing the size of openings of fittings where standard fittings of the required size are not available.

2-4.2.5 All threads used in jo ints and fittings shall conform to ANSI B1.20.1, Pipe Threads, General Purpose (Inch). Jo in t compound , tape, or thread lubricant shall be applied only to the male threads of the joint.

2-4.2.6 Soldering fluxes shall be in accordance with Table 2-3.2.1. Brazing fluxes, if used, shall no t be of a highly corrosive type.

2-4.2.7 Welding shall be pe r fo rmed in accordance with AWS D10.9, Specification for Qualification of Welding Procedures and Welders~or Piping and Tubing~ Level AR-3.

2-4.3 Intermediate and High Pressure Systems.

2-4.3.1 Fittings shall have a m i n i m u m rated working pressure equal to or greater than the m a x i m u m operat ing pressure of the water mist systems at 130°F (54°C). For systems that employ the use of a dPressure regulat ing device in the distr ibution piping, the fittings

ownstream of the device shall have a m i n i m u m rated working pressure equal to or greater than the m a x i m u m anticipated pressure

the downst ream piping.

2-4.3.2 All threads used in jo in ts and fittings shall conform to ANSI B1.20.1, Pipe Threads, General Purpose (Inch). Jo in t compound , tape, or thread lubricant shall be apphed only to/_he male threads of the joint .

2-4.3.3 Welding and brazing alloys shall have a mel t ing poin t above 1000°F (538°C).

2-4.3.4 Welding and brazing shall be pe r fo rmed in accordance with Section IX of the ASME Boiler and Pressure Vessel Code.

2-4.3.5 Where copper, stainless steel, or o ther suitable tubing is j o ined with compression-type fittings, the manufac tu re r ' s pressure tempera ture ratings for the fitting shall no t be exceeded.

2-5 Hangers.

2-5.1 Hangers shall be listed for use with the pipe or tube involved.

Exception: Hangers certified by a registered professional engineer to include the following shall be permitted where:

(a) Hangers are designed to support five times the weight of the pipe or tube when filled with gas or water, as appropriate, plus 250 lb (114 kg) at each point of piping support;

(b) These points of support are adequate to support the water mist system; and

( c ) Hanger components are ferrous.

Detailed calculations shall be submitted, where required by the authority having jurisdiction, showing the stresses developed both in the hangers and the piping and the safe~y factors provided.

2-5.2 Hanger componen t s shall be ferrous.

Exception: Nonferrous components that have been proven by fire tests to be adequate for the hazard application, that are listed for this purpose, and that are in comph'ance with the other requirements of this section shall be permitted.

2-5.3 The componen t s of hange r assemblies tha t attach direcdy to the pipe or to the building structure shall be listed. Th readed port ions of hangers shall no t be bent.

Exception: Mild steel rods that connect pipe and building attachment components shall be permitted to be of an approved ~ype.

N F P A 750 m A96 R O P

2-5.4 The use of listed inserts set in concrete to suppor t hangers shall be permit ted.

2-5.5 Power-driven fasteners shall no t be used to attach bangers to the building structure where systems are required to be protected against earthquakes.

Exception: Power-driven fas.teners shall be permitted where they are specificall~ listed for service in seismic areas.

2-6 Nozzles.

2-6.1" Nozzles shall be listed either individually or as a part of a pre- eng ineered system. Listing informat ion shall include:

(a) Volumetric flow rate characteristics of water discharge for each nozzle.

(b) Max imum he igh t of protected space.

(c) M i n i m u m distance between nozzle tip or diffuser, as applicable, and plane of protection.

(d) M a x i m u m spacing between nozzles.

(e) M a x i m u m coverage area per nozzle.

(f) M i n i m u m spacing between nozzles.

(g) Max imum he igh t between ceiling and nozzle diffuser or tip, as applicable.

(h) Nozzle obstruction spacing criteria.

(i) Max imum spacing of nozzles f rom walls.

(j) Min imum and m a x i m u m rated operat ing pressures of nozzles.

(k) Allowable range of nozzle orientat ion angle f rom vertically down.

(I) Classification of automat ic nozzle thermal response characteristics as fast, special, or s tandard response.

(m) M a x i m u m c o m p a r t m e n t volume, if applicable.

2-6.2 Only new nozzles shall be installed in water mist systems.

2-6.3 Nozzles shall be pe rmanen t ly marked to identify the manufacturer, type, and size of the orifice(s) or part number .

2-6.4 Additional corrosion protection, such as special corrosion- resistant materials or coatin~gs, shall be required-in severely corrosive a tmospheres .

2-6.5 Where clogging by external foreign materials is likely, discharge nozzles shall be provided witfi frangible discs, blow-off caps, or o ther suitable devices. These device~shall provide an unobs t ruc ted open ing upon system operat ion and s]lall be located so they canno t injure personnel .

2-6.6 The s tandard t empera tu re ratings o f individual, thermally- activated nozzles are shown in Table 2-6.6. Individual, thermally- activated nozzles shall be colored in accordance with the color code designated in Table 2-6.6.

2-6.7 The stock of spare, individual, thermally-activated nozzles shall include all types and ra t i ngs installed and sball be as follows:

(a) For systems having fewer than 50 nozzles, not fewer than 3 nozzles;

(b) For systems having 50 to 300 nozzles, no t fewer than 6 nozzles;

(c) For systems having 301 to 1000 nozzles, no t fewer than 12 nozzles;

(d) For systems having over 1000 nozzles, no t fewer than 24 nozzles.

2-7 Valves.

2-7.1 All valves shall be listed for their in tended use.

Exception: Valves used onO for drains or test connections shall be permitted to be approved.

2-7.2 All gaskets, O-rings, sealants, and o ther valve componen t s shall be const ructed of materials that are compatible with the gas or water and any additives conta ined in the water_

2-7.3 Special corrosion-resistant materials or coatings shall be used in severely corrosive a tmospheres .

2-7.4 Identification o f Valves. All control, drain, an d test connec- t ion valves shall be provided with p e r m a n e n d y marked, weatherproof, metal or rigid plastic identification signs.

2-8 Strainers and Filters.

2-8.1 Pipeline strainers and filters shall be listed for use in water supply connect ions.

2-8.2 The strainer or filter shall be capable of con t inued operat ion without serious increase in head loss for a period e s t ima ted to be ample, taking into accoun t the type of protect ion provided, the condit ion of the water, and similar local circumstances.

2-8.3 Pipeline strainer and filter designs shall incorporate a flush- out connect ion.

2-8.4 Pipeline strainers and filters shall be sized in accordance with 7-6.1.2 and Table %6.1.2.

2-8.5 Individual strainers or filters for water mist nozzles, where required by the manufacturer , shall be listed as a part of a nozzle.

2-8.6 A stock of spare pipeline and individual nozzle strainers and filters for water mist nozzles shall be provided and shall include all types and sizes installed. Sufficient spare strainers and filters shall be provided to service the nozzles for the largest single hazard or group of hazards to be protected simultaneously.

2-9 Pumps.

2-9.1 Materials.

2-9.1.1 Pumps shall have adequate capacities to mee t the m a x i m u m system demand .

Table 2-6.6 Temperature Ratings, Classifications, and Color Coding of Individual, Thermally-Activated Nozzles

Maximum Ambient Temperature

CF) (°c)

100 38

150 66

225 107

300 149

375 191

475 246

625 329

Nozzle Temperature Rating

135 to 170 57 to 77

175 to 225 79 to 107

250 to 300 121 to 149

325 to 375 163 to 191

400 to 475 204 to 246

500 to 575 260 to 302

650 343

Temperature Clamafication

Ordinary

Intermediate

High

Extra high

Very extra high

Ultra h igh

Ultra high

Color Code

Uncolored or black

White

Blue

Red

Green

Orange

Orange

Class Bulb Colors

Orange or tRed

Yellow or g reen

Blue

Purple

Black

Black

Black

672

N F P A 7 5 0 - - A 9 6 R O P

2-9.1.2 Pumps capable of overpressurizing the system shall b e provided with adequate means of pressure relief from the discharge to the supply side of the pump to prevent excessive pressure and temperature. Overpressure shall not exceed the working pressure of the piping system.

2-9.1.3 Pumps shall start antomatically upon system actuation.

2-9.1.4 Provisions shall be made for automatic shutoff of the pump after the water supply is exhausted.

2-9.1.5 Pumps shall not take suction under a static lift condition.

2-9.2 Power Supply.

2-9.2.1 The power supply' for pump drivers shall be installed in accordance with NFPA 20, Standard for the Installation of Centrifugal Fire Pumps, and NFPA 70, National Electrical Code.

Exception: Power supplies shall not be required to be fed by an independent service feed.

2-9.2.2 Power supplies shall be arranged so that disconnecting power to the protected facility during a fire shall not disconnect the power supply to the pump feeder circuit.

2-9.3 Controllers.

2-9.$.1 Controllers for pumps shall be listed as follows:

(a) Electric drive pumps greater than 30 horsepower, listed fire pump controller;

(b) Electric drive pumps greater than 15 horsepower but not exceeding 30 horsepower, listed fire pump controller or listed limited service controller;

(c) Electric drive pumps less than 15 horsepower, listed limited service controller;

(d) Diesel engine drive pumps, listed fire pump controller.

2-9.3.2 A service disconnecting means in the feeder circuit to limited service controllers shall be permit ted where permit ted by the authority having jurisdiction, provided the disconnecting means is supervised for the proper position. Supervision for proper position shall be by one of the following methods:

(a) Central station, proprietary, or remote station signaling electrical supervision service; or

(b) Local electrical supelMsion through use of a signaling service that causes the sounding of an audible signal at a constantly a t tended location; or

(c) Locking of the disconnecting means in the proper position, with monthly recorded inspections.

2-10 Detection, Actuation, Alarm, and Control Systems.

2-10.1 General.

2-10.1.1 Detection, actuation, alarm, and control systems shall be installed, tested, and maintained in accordance with appropriate protective signaling systems standards as follows:

NFPA 70, National Electrical Cod~

NFPA 72, National Fire AIz~rm Codg

CAN/ULC $524-M86, Standard for the Installation of Fire Alarm Systems (in Canada);

CAN/ULC $529-M87, Smoke Detectors for Fire Alarm Systems (i n Canada).

2-10.1.2 Where a detection system is used to actuate the water mist system, detect ion and actuation shall be automatic.

Exception: Manual-only actuation shall be permitted if approved by the authori 0 having jurisdiction.

2-10.1.3 All wiring systems shall be installed in conduit or raceway and in accordance with NFPA 70, NationalElectrical Coda

2-10.2 Automatic Detection.

2-10.2.1" Automatic detection shall be by listed equipment installed in accordance with NFPA 72, NationalFireAlarm Coda

2-10.2.2 Adequate and rel iableprimary and 24-hour minimum standby sources of energy shall be used to provide for operation of the detection, signaling, control, and actuation requirements of the systems.

2-10.2.$ f i n n existing detection system is used in a new water mist system, the detection system shall comply with the requirements of this standard.

2-10.3 Operating Devices.

2-10.3.1 Operat ing devices shall include water mist releasing devices or valves, discharge controls, and shutdown equipment necessary for successful performance of the system.

2-10.3.2 Operat ion shall be by listed mechanical, electrical, or pneumatic equipment. An adequate and reliable source of energy shall be used.

2-10.3.3 Devices shall be designed for the service they are to encounter and shall not readily be rendered inoperative or susceptible to accidental operation. Devices shall be designed to function properly from-20°F to 130°F (-29°C to 54°C) or shall be marked to indicate temperature limitations.

2-10.3.4 Devices shall be located, installed, or suitably protected so they are not subject to mechanical, chemical, or other damage that could render them inoperative.

2-10.3.5 An emergency release of the system that can be achieved by a single manual operation shall be provided. This shall be accom- plished by a mechanical manual release, or by an electrical manual release when the control equipment that monitors the battery voltage level of the standby battery supply indicates a low battery signal. The release shall cause simultaneous operation of automatically operated valves that control agent release and distribution. The battery shall be sized to accomplish all functions.

Exception: Dry and wet pipe systems utilizing individuag thermally-activated nOZZ~S.

2-10.$.6 The normal manual control(s) for actuation shall be located for easy accessibility at all times, including at the time of a fire. The manual control(s) shall be of distinct appearance and clearly recognizable for the purpose intended. Operat ion of any manual control shall cause the complete system to operate in its normal fashion.

2-10.3.7 Manual controls shall not require a force of more than 40 lbf (178 N) nor a movement of more than 14 in. (356 mm) to secure operation. At least one manual control for activation shall be located not more that 4 ft (1.2 m) above the floor.

2-10.$.8 All devices for shutt ing down supplementary equipment shall be considered integral parts of the system and shall function with the system in operation.

2-10.3.9 All manual devices shall be identified as to the hazard they protect.

2-10.4 Control Equipment.

2-10.4.1 Electrical Control Equipment. Automatic control equipment shall be listed and installed in accordance with NFPA 72, National Fire Alarm Coda

2-10.4.2 The control uni t shall be listed for release device service.

2-10.4.3 Pneumatic Control Equipment.

2-10.4.3.1 Pneumatic control lines shall be protected against crimping and mechanical damage. Where installations could be exposed to conditions that could lead to loss of integrity of the

[ lines, special precautions shall be taken to ensure that no ss of integrity occurs. Pneumatic control lines used as part of the

system actuation shall be supervised.

2-10.4.3.2 The control equipment shall be specifically listed for the number and type of actuating devices utilized, and their compatibility shall have been listed.

673

NFPA 750 - - A96 ROP

2-11 Unwanted System Operation. Care shall be taken to thoroughly evaluate and correct any factors that could result in unwanted system discharge.

2-12 Compatibility. All components of pneumatic, hydraulic, or electrical systems shall be compatible.

Chapter 3 System Requirements

3-1 General. Water mist systems sball be described by the following four parameters:

(a) System application;

(b) Nozzle type;

(c) System operation method; and

(d) System media type.

3-2 System Applications. System applications shall consist of the following three categories:

(a) Local application systems;

(b) Total compar tment application systems; or

(c) Zoned application systems.

3-2.1 Local Application Systems. Local application systems are designed and installed to provide complete distribution of mist around the bazard/objec t to be protected.

3-2.1.1 Local application systems shall be designed to protect an object or a hazard in an enclosed, unenclosed, or open outdoor condition.

3-2.1.2 Local application systems shall be actuated by automatic nozzles or by an independen t detection system.

3-2.2 Total Compartment Application Systems. Total compar tment application systems are designed and installed to provide complete protection of an enclosure/space.

3-2.2.1 The complete protection of the enclosure/space shall be achieved by the simultaneous operation of all nozzles in the space by manual or automatic means.

3-2.2.2 The simultaneous operation of all nozzles in the space shall be achieved by the use of automatic nozzles or by an independen t detection system.

3-2.3 Zoned Application Systems. Zoned application systems are a subset of the compar tment system and are designed to protect a predetermined portion of the compar tment by the activation of a selected group of nozzles.

3-2.3.1 Zoned application systems shall be designed and installed to provide complete mist distribution throughout a prede termined portion of the enclosure/space. This shall be achieved by simultaneous operation of a selected group of nozzles in a prede termined portion of tile space by manual or automatic means.

3-2.3.2 Zoned application systems shall be actuated by automatic nozzles or by an independen t detection system.

3-3 Nozzle Types. Water mist nozzles shall be classified as one of the following three types:

(a) Automatic;

(b) Nonautomatic; and

(c) Hybrid.

3-3.1 Automatic Nozzles. Automatic nozzles shall operate indepen- dently of other nozzles by means of a detection/activation device built into the nozzle.

3-3.2 Nonautomatic Nozzles (Open). Nonautomatic nozzles shall operate as an entire system or grouping of nozzles. These nozzles contain open orifices and the water flow to the nozzles shall be activated by an independen t detection system.

3-3.3 Hybrid Nozzles. A hybrid nozzle shall operate using a combination of tbe two methods described previously (automatic or nonautomatic means, or both). These nozzles contain a built-in detection/activation device that also can be activated by an independen t detection system.

3-4 System Operation Methods. Water mist systems shall operate by means of one of the following methods:

(a) Deluge;

(b) Wet pipe;

(c) Preaction; and

(d) Dry pipe.

3-4.1 Deluge Systems. Deluge systems shall employ nonautomatic nozzles (open) attached to a piping network connected to the fluid supply(ies) through a valve conlrolled by an independen t detection system installed in the same area as the mist nozzles. When the valve(s) is activated, the fluid shall flow into the piping network and discharge from all nozzles attached thereto.

3-4.2 Wet Pipe Systems. Wet pipe systems shall employ automatic nozzles attached to a piping network pressurized with water up to the nozzles.

3-4.3 Preaction Systems. Preaction systems shall employ automatic nozzles at tached to a piping network containing a pressurized gas with a supplemental independen t detection system installed in the same area as the nozzles. Operation of the detection system shall actuate a tr ipping device that opens the valve, pressurizing the pipe network with water to the nozzles.

3-4.4 Dry Pipe Systems. Dry pipe systems shall employ automatic nozzles at tached to a piping network containing a pressurized gas. The loss of pressure in the piping network shall activate a control valve, which causes water to flow into the piping network and out through the activated nozzles.

3-5 Media System Types. Water mist systems shall be classified by two media system types:

(a) Single fluid; or

(b) Twin fluid.

Both types of systems can be operated in the low, intermediate, or high pressure range.

3-5.1 Single Fluid Media Systems. Single fluid media systems need only one set of distribution piping to t ransport the fluid to each nozzle.

3-5.1.1 Single fluid media systems shall produce water mist (droplet production) by one of the means specified in 3-5.1.1.1 through 3-5.1.1.5.

3-5.1.1.1 Liquid shall be discharged at a high velocitywith respect to the surrounding air. The difference in velocities between the liquid and surrounding air shall shear the liquid into small droplets. Examples of this technology include plain orifice, swirl, and simplex atomizers.

3-5.1.1.2 A liquid stream is impinged upon a fLxed surface. The impact of the liquid on the surface breaks the liquid stream into small droplets.

3-5.1.1.3 Two liquid streams of similar composition collide upon one another. The collision of the two streams breaks the individual streams into small droplets.

3-5.1.1.4 Liquid is either vibrated or electrically broken into small droplets (ultrasonic and electrostatic atomizers).

3-5.1.1.5 Liquid is heated above its boiling point in a pressurized container and released suddenly to atmospheric pressure (flashing liquid sprays).

3-5.2 Twin Fluid Media Systems.

3-5.2.1 Twin fluid media systems need two sets of distribution piping to be attached to each nozzle. One set of piping provides a liquid (water) to the nozzle, with the second piping network providing an atomizing f luid/media.

674

N F P A 750 ~ A 9 6 R O P

3-5.2.2 Twin fluid media systems produce water mist (droplet production) by exposing a slow-moving liquid to a h igher velocity atomizing fluid s tream. The process shall occur in or near the discharge nozzle.

Chapter 4 Installation Requirements

4-1 General. This chapter provides requi rements for the correct installation of water mist system components .

4-1.1 All materials and devices essential to the successful operat ion of the system shall be listed.

4-1.2 System componen t s shall be rated for the m a x i m u m working pressure to which they are exposed.

4-2 Nozzles.

4-2.1 General. Nozzles shall be installed in accordance with the manufac ture r ' s listing.

4-2.2 Nozzle Height Limitations. The m i n i m u m and m a x i m u m heights shall be in accordance with the manufac tu re r ' s listing.

4-2.3 Nozzle Spacing Limitations. The m i n i m u m and m a x i m u m distances between nozzles shall be in accordance with the manufac tu re r ' s listing.

4-2.4 Distance from Walls. The distance f rom nozzles to walls shall no t exceed one-haft of the permit ted distance between nozzles.

4-2.5 Obstructions to Nozzle Discharge. The location of nozzles with respect to obstruct ions shall be in accordance with the manufac tu re r ' s listing.

4-2.5.1 Horizontal Obst ruc t ion~ Nozzles shall be installed unde r ducts, decks, and other obstruct ions larger than the size identified in the manufac tu re r ' s listing.

4-2.5.2 Clear Space Below Nozzles. A m i n i m u m clearance between the nozzle orifice and obstruct ions below the nozzle or the top of storage shall be main ta ined in accordance with the manufac ture r ' s listing.

4-2.6 Distance Below Ceilings. The distance between the nozzle and the ceiling shall be in accordance with the range ( m i n i m u m and max imum) identified in manufac tu re r ' s listing.

4-2.7 Spacing under Pitched or Curved Surfaces. The distance between nozzles ih or u n d e r a p i tched or curved surface shall be in accordance with the manufac tu re r ' s listing.

4-2.8 Nozzle Protection. Nozzles subject to mechanical injury shall be protected with listed guards. This guard shall no t significantly reduce the effectiveness of the nozzle.

4-2.9 Escutcheon Plates.

4-2.9.1 Escutcheon plates used in a recessed or flush-type nozzle installation shall be a part of a listed nozzle assembly.

4-2.9.2 Nonmetal l ic escutcheon plates shall be listed.

4-2.10 Automatic Nozzle Temperature Ratings

4-2.10.1 Ordinary temperature-ra ted nozzles shall be used unless otherwise specified.

4-2.10.2 The following practices shall be observed where providing automatic nozzles of o ther than ordinary tempera ture classification unless o ther tempera tures are de t e rmined or unless high temperature nozzles are used th roughout .

(a) Automatic nozzles installed in a heater zone shall be of the h igh t empera tu re classification, and nozzles in the danger zone shall be of the in termediate t empera tu re classification.

(b) Automat ic nozzles located within 12 in. (305 ram) to one side of or 30 in. (762 ram) above an uncovered s team main, hea t ing coil, or radiator shall be of the intermediate t empera ture classification.

(c) Automat ic nozzles within 7 ft (2.1 m) of a low pressure blow-off valve that discharges freely in a larger room shall be of the high t empera tu re classification.

(d) Automat ic nozzles installed u n d e r glass orplast ic skylights exposed to the direct rays of the sun shall be of the intermediate t empera tu re classification.

(e) Automat ic nozzles installed in an unventi lated, concealed

R ace, u n d e r an insulated roof, or in an unvent i la ted attic shall be of e in termediate t empera tu re classification.

(f) Automatic nozzles installed in unvent i la ted areas having high- powered electric lights near the ceiling shall be of the in termediate t empera tu re classificafion.

(g) Automat ic nozzles protect ing commercial-type cooking equ ipmen t and ventilation systems shall be of the high or extra h igh t empera tu re classification as de t e rmined by use of a t empera ture measur ing device.

4-3 Piping and Tubing.

4-3.1 Piping mad tubing for water mist systems shall be installed in accordance with the manufac tu re r ' s listing or shall comply with the following, or both:

(a) The water piping for low pressure water mist systems shall conform to NFPA 13, Standard for the Installation of Sprinkler Syster~,

(b) The water piping for in termediate or h igh pressure water mist systems, and the atomizing media piping for all twin fluid systems, shall be installed in conformance with ANSI B31.1, Power Piping Coda

4-3.1.1 All system piping, tubing, and hoses shall be rated for the m a x i m u m working pressure to which they are exposed.

4-3.1.2 Any flexible piping, tubing, hoses, or combinat ion thereof shall be const ructed and installed in accordance with the manufac ture r ' s listing.

4-3.2 The system piping shall be suppor ted by structural e lements that are i ndependen t o f the ceiling shea th ing to prevent lateral and horizontal movemen t u p o n system actuation.

4-3.3 All system piping and fittings shall be installed so that the entire system can be drained.

4-3.4 Location of Hangers and Supports.

4-3.4.1 Hangers and supports shall be installed in accordance with the manufac tu re r ' s listing.

Exception: Steel pipe and copper tubing shall be supported in accordance with NFPA 13, Standard for the Installation of Sprinkler Systems.

4-3.4.2 The length of an u n s u p p o r t e d arm over to a nozzle shall no t exceed 2 ft (0.6 m) for steel pipe or 1 ft (0.3 m) for steel tubing.

4-3.5 Types o f Hangers . All hangers shall be of the listed type.

4-3..6 Protection of System Components against Damage where Subject to Earthquakes. Water mist systems shall be protected to prevent pipe breakage where subject to ear thquakes in accordance with 4-6.4.3 of NFPA 13, Standard for the Installation of Sprinkler Systems.

4-4 Fittings.

4-4.1 All system fittings shall be installed in accordance with the manufac ture r ' s listing.

Exception: A ll fittings installed in low pressure water mist ssstems shall conform to NFPA 13, Standard for the Installation of Sprinkler 5)stems.

4-4.2 All fittings shall be of the listed type.

44 .3 All fittings shall be rated for the m a x i m u m working pressure to which they are exposed.

4-5 Gas and Water Storage Containers.

4-5.1 Storage containers shall be installed, moun ted , and braced in accordance with the manufac tu re r ' s listing.

4-5.2 Storage containers and accessories shall be installed so that inspection, testing, recharging, and o ther ma in tenance are facilitated and interrupt ion to protect ion is he ld to a min imum.

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N F P A 750 1 A 9 6 R O P

4-5.3 Storage containers shall be located as near as possible to the hazard or hazards they protect bu t shall no t be installed in areas exposed to the tire.

4-5.4 Storage containers shall be protected fi-om severe weather condit ions and f rom mechanical , chemical, or o ther damage.

4-5.4.1 Where excessive climatic or mechanical exposures are expected, listed guards or enclosures shall be provided.

4-5.4.2 A reliable means shall be provided to indicate the pressure and level in all s torage containers.

4-5.5 High Pressure Storage Containers.

4-5.5.1 High pressure containers or cylinders shall be constructed, tested, and-marked in accordance with U.S. Depa r t men t of Transpor ta t ion Title 49, Code of Federal Regulations, Parts 171 to 190, Sections 178.36 and 178.37, specifications (in effect upon date of manufac ture and test) for DOT-3A, 3AA-1800, or higher, seamless steel cylinders. Charged cylinders shall be tested for t ightness before sh ipmen t in accordarice with an approved procedure.

4-5-5.2 High pressure cylinders used in fire ext inguishing systems shall no t be recharged without a hydrostatic test (and remarking) if more than 5 years have elapsed f rom the date of the last test. Cylinders tha t have been in con t inuous service without discharging shall be permi t ted to be re ta ined in service for a m a x i m u m of 12 years, after which they shall be d ischarged and retested before being r e tu rned to service.

4-5.5.3 Each cylinder shall be provided with a safety device to relieve excess pressures safely before they exceed the rated cylinder test pressure.

4-5.5.4 Where manifolded, cylinders shall be adequately m o u n t e d and suitably suppor ted in a rack provided for this purpose, including facilities for convenient individual servicing or weighing of contents. W h e n any cylinder is removed for main tenance , automat ic means shall be provided to prevent leakage f rom the manifo ld if the system is operated.

4-5.5.~ Storage tempera tures shall no t exceed or fall below the manufac tu re r ' s listed limits. External hea t ing or cooling shall be used to mainta in the t empera tu re of the storage conta iner within the desired limits.

Exception: Heated water extinguishing systems that store permanently superheated liquid shall be maintainedat their minimum operating temperature by means of a listed internal heating element and automatic temperature regulating device.

4-5.6 Low Pressure Storage Cylinders

4-5.6.1 The pressure container shall be made, tested, approved, equipped, and marked in accordance with the cur ren t specifications of the A,SME Boiler and Pressure Vessel Code, Section VIII, or the requi rements of Depa r tmen t of Transpor ta t ion Title 49, Code of FederalRegulations, Parts 171 to 190, Sections 178.36 and 178.37, or both. The design working pressure shall be in accordance with the manufac tu re r ' s listing.

Exception: Pressure containers for heated water extinguishing systems shall be in accordance with the manufacturer's listing.

4-5.6.2 Each pressure conta iner shall be equ ipped with a liquid level gauge, a pressure gauge, and a h i gh / t ow pressure supervisory alarm set at the values identif ied in the manufac tu re r ' s listing.

Exception: Media storage containers that become pressurized only during system activation shall not require high~low pressure superviso~ d alarms.

4-5.7 Storage tempera tures shall no t exceed or fall below the manufac tu re r ' s listed limits. External hea t ing or cooling shall be used to mainta in the tempera ture of the storage conta iner within the desired limits.

Exception: Heated water ~xtinguishing systems shall be maintained at their minimum operating temperature by means of a listed internal heating element and automatic temperature regulating device.

4-6 Pumps and Pumps Controllers

4-6.1" Pumps shall be sized to provide 120 percent of the required system water flow rate, at the m i n i m u m system operat ing pressure, as de t e rmined by hydraulic calculations.

676

4-6.2 Pumps shall start automatically and shall supply water to tile water mist system until manual ly shu t off or automatically shu t off in accordance with the manufac tu re r ' s listing.

4-6.3 Power supplies for system p u m p s shall mee t the requirements spe cifi ed i n NFPA 20, Standard for the Installation of Centrifugal Fire Pumps, or shall be in accordance with the manufac ture r ' s listing.

4-6.4 Pumps shall be provided with supervisory service f rom a listed central station, proprietary, or remote station system or equivalent.

Exception: Pumps for single family dwellings.

4-7 Strainers and Filters.

4-7.1 Filters shall be provided at all connect ions to sources of water. Filters shall be des igned to minimize potential head loss due to the accumula t ion of particulates. At a m in imum, all system filters shall be des igned to operate for a m i n i m u m of 30 minutes u n d e r condit ions of the mos t severe ant icipated water quality (as deter- m ined by the authori ty having jurisdict ion) without a degradat ion of the water mist system performance.

Exception: Self-contained systems constructed of noncorrosive materials shall not require in-line filtration.

4-7.2 Strainers. A listed strainer shall be provided in the riser or feed main that supplies water mist nozzles. The strainer shall inhibit the passage of particulates larger than 70 percen t of the free passage orifice area.

4-8 Valves and Pressure Gauges.

4-8.1 General.

4-8.1.1 All valves shall be installed and or iented in accordance with the manufac tu re r ' s listing.

4-8.1.2 Valves having componen t s tha t ex tend beyond the valve body shall be installed in a m a n n e r tha t does no t interfere with the operat ion o f any system components .

4-8.1.3 All valves shall be listed for their particular application and installation.

4-8.1.4 All control, drain, and test connec t ion valves shall be provided with p e r m a n e n d y marked, weatherproof, metal or rigid plastic identification signs. The sign shall be secured by corrosion- resistant wire or chain or by o ther approved means.

4-8.1.5 System valves and gauges shall be accessible for operation, inspection, and main tenance . Valves shall be installed within a l ighted and hea ted space to prevent freezing. (See 4-8.2.4.)

4-8.1.6 At least one listed indicating valve shall be installed in each source of water supply.

Exception: Systems with a single water supply source composed of a self- contained system (cylinders, containers).

4-8.1.7 Valves on connect ions to water supplies, sectional control valves, and other valves in supply pipes to nozzles shall be locked open or equipped with t amper moni to r ing devices.

4-8.2 Control/Activation Valves.

4-8.2.1 Control /act ivat ion valves shall include any device or valve tha t automatically opens to supply water to the nozzles after the detect ion of a fire.

4-8.2.2 Control /act ivat ion valves shall operate by a listed mechani - cal, electrical, or pneumat i c means. An adequate an d reliable source of energy shall be used.

4-8.2.3 Control /act ivat ion valves shall be des igned for the service they are to encoun te r and shall no t be readily r endered inoperative or susceptible to accidental operation.

4-8.2.4 Control /act ivat ion valves shall be located, installed, or suitably protected so that they are no t subject to mechanical , chemical, or o ther damage that could render them inoperative.

4-8.3 Pressure Regulating/Rellef Valves.

4-8.3.1 Water Pressure Regulating Valves.

N F P A 7 5 0 - - A 9 6 R O P

4-8.3.1.1 Pressure regulat ing valves shall be installed in any port ion of the system where the potential exists for the system pressure to exceed the m a x i m u m rated working pressure of the system or system components , or both. These valves shall open when the system pressure reaches 95 percen t of the system rated pressure.

4-8.3.1.2 Pressure regulat ing valves shall be installed on the discharge side of all pumps .

4-8.3.1.3 Pressure regulat ing valves shall be installed on any system c o m p o n e n t operat ing at a h igher pressure than the rated system pressure.

4-8.3.1.4 A relief valve of no t less than 1 /2 in. (13 mm) shall be provided on the discharge side of the pressure regulat ing valve that is set to operate at a pressure not exceeding the system rated pressure.

4-8.3.1.5 A listed indicating valve shall be provided on tbe inlet side of each pressure reduc ing valve.

Exception: A listed indicating valve shall not be required where the pressure regulating valve meets the lis ring requirements for use as an indicating valve.

4-8.3.1.6 A water flow test valve sized to p roduce the des igned flow of the pressure reduc ing valve shall be installed on the downst ream side of the pressure reduc ing valve.

4-8.3.1.7 A sign shall be a t tached to the pressure reducing valve indicating the correct discharge pressure for static and residual pressures.

4-8.3.2 Air Pressure Regulating Valves. (Content to be de te rmined)

4-8.4 Check Valves and Backflow Preventers

48.4.1 Check valves shall be installed in a vertical or horizontal position in accordance with the manufac tu re r ' s listing.

48.4 .2 A check valve shall be installed between the system and the point of p e r m a n e n t connect ion to a potable water supply.

Exception: Where additives are used in the water mist system, either by injection into flowing lines o'r by premixing into stored water sources, a backflow preventer shall be installed between the system control valve or stored water supply and a permanent connection to a potable water supply.

48.4.3 Check valves shall be installed in the main feed lines, near the control valves of both the water and pneumat i c system piping of a twin fluid system, to prevent the backflow of water or atomizing fluid into the compan ion piping.

48 .5 Pressure Gauges. All pressure gauges shall be installed and or iented in accordahce with the manufac tu re r ' s listing.

48.5.1 The required pressure gauges shall be listed for their i n t ended use a n d sha l /h~ve an operat ing range not less than twice the normal working pressure of the system.

48 .5 .2 Pressure gauges shall be installed in the following locations:

(a) On both sides of a pressure regulat ing valve;

(b) On the pressurized side of all supply connections;

(c) O n fl~e pressurized side of all system control valves;

(d) O n all pressurized storage containers; and

(e) On all air supplies for dry pipe and preact ion systems.

4-9 Detection and Actuation Systems.

4-9.1 Electrical Equipment.

4-9.1.1 Water mist system wiring shall mee t the requi rements of IEEE 45, Recommended Practice for Electric Installations on Shipboard. Wiring shall be secured in compact harnesses and a t tached to f rame member s with insulated clamps at close intervals to ensure a nea t and orderly cable run. Cables and wires shall no t be spliced at any point t h roughou t the length of, their runs. Wiring shall no t be a t tached to panels or o ther componen t s that need to be removed dur ing main tenance , except for actual electrical connect ions to components . Electrical isolators shall be used between all wiring and metal componen t s to prevent abrasive action to wire insulation. Wiring shall be color coded or n u m b e r e d for easy identification and shall be consistent with the existing wiring.

4-9.1.2 The water mist system electrical componen t s shall be compatible with the electric power system characteristics.

4-9.1.3 Bonding, g rounding , and o ther techniques, such as the use of nonmetal l ic materials, tha t are employed to reduce EMI shall be in accordance with the requ i rements of MIL~TD-131 0, Shipboard Bonding, Grounding, and Other Techniques for Electromagnetic Compatibil- ity and Safety.

4-9.1.4 AC motors shall have locked rotor currents as low as practical in order to prevent excessive voltage fluctuations. Three- phase motors shall be selected for operat ion with 240-volt alternat- ing current . Use of single-phase motors shall be l imited to those of 1 horsepower or less.

4-9.1.5 The electrical componen t s that pressurize the system shall have a m i n i m u m Ingress Protection Rating of 54 (IP 54) as specified by the Internat ional Electrotechnical Commission.

4-9.1.6" All system componen t s shall be located to mainta in m i n i m u m clearances f rom energized electrical parts.

4-9.1.7 All system circuits and wiring shall be fail-safe so tha t any single open or g r o u n d fault on any circuit or conduc tor does not cause system impa i rmen t but instead causes a t rouble signal.

Exception: Conductors to existing motors and conductors within enclosures.

4-9.2 Control Equipment.

4-9.2.1 Alarms shall be provided that indicate system activation or system trouble conditions, or both. Trouble signals shall include power failure, operat ion (closing) of mon i to red valving, and electrical faults in the detect ion/act ivat ion of p u m p power control systems. These alarms shall be both visible and audible inside the protected space, at the location of the pr imary system componen t s (e.g., pumps, storage tanks), and in a cont inuously a t t ended location. The alarm for activation shall be distinctly different f rom the trouble alarm to prevent confusion.

4-9.2,2 The alarm, actuation, and control systems shall be installed in accordance with NFPA 70, NationalElectrical Code, NFPA 72, NationalFireAlarm Code or equivalent, or the manufac turers ' r ecommendat ions , as appropriate.

4-9.2,3 All circuitry moni to r ing or controll ing tile water mist system shall be electrically supervised in accordance with NFPA 72, National Fire Alarm Coda

4-9.2.4 Adequate and reliable primary and 24-hour m i n i m u m standby sources of energy shall be used to provide for operat ion of the detection, signaling, control, ,and actuat ion requ i rements of the system.

4-9.3 Automatic Detection.

4-9.3.1" Automat ic detect ion shall be byany listed m e t h o d or device capable of detect ing and indicating heat, flame, smoke, combustible vapors, or an abnormal condi t ion in the hazard, such as process trouble, that is likely to produce fire.

4-9.3.2 Adequate and reliable pr imary and 24-hour m i n i m u m standby sources of energy shall be used to provide for operat ion of the detection, signaling, control, and actuat ion requi rements of the system.

4-9.3.3 Where a new water mist system is installed in a space that has an existing detection system, an analysis shall be m a d e of the detect ion devices to ensure daat the detect ion system meets the requi rements of the water mist system listing and that the detect ion system is in good operat ing condit ion.

4-9.4 Manual Activation.

4-9.4.1 A means for manua l release of the system shall be provided. This shall be accompl ished by a mechanical manua l release, or by an electrical manua l release when the control e q u i p m e n t that moni tors the battery voltage level of the s tandby battery supply indicates a low battery signal. The release shall cause s imul taneous operat ion of automatically operated valves that control agen t release and distribution.

4-9.4.2 The normal manua l control(s) for actuat ion shall be located for easy accessibility at all times, including at the t ime of a fire. The manua l control(s) shall be of distinct appearance and clearly

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N F P A 750 - - A96 R O P

recognizable for the purpose in tended. Opera t ion of any manua l control shall cause the complete system to operate in its normal fashion.

4-9.4.3 Manual controls shall no t require a force of more than 40 lbf (178 N) nor a m o v e m e n t of more than 14 in. (356 ram) to secure operation. At least, one manua l control for activation shall be located not more than 4 ft (1.2 m) above the floor.

Chapter 5 Design Objectives and Hazard Classifications

5-1 General. Currently, no general design me t hod is recognized for water mist protect ion systems. Water mist protect ion systems shall be designed and installed in accordance with their listing for the specific hazards and protect ion objectives specified in the listing. Tile cbaracteristics o f the specific application ( compar tmen t variables and hazard classification) shall be consistent with the listing of the system. The c o m p a r u n e n t geometry, fire hazard, and system variables described in dais chapter shall be considered adequate to ensure that tile system design and installation are consistent with the system listing.

5-1.1 The fire-fighting per formance objectives of a water mist system shall be descr ibed us ing the following three terms:

(a) Control;

(b) Suppression; and

(c) Ext inguishment .

5-1.1.1 Fire Control. Fire control can be measu red using dl ree basic approaches:

(a) A reduct ion in the thermal exposure to the structure, where tile primary objective is to mainta in tile structural integrity of the bui lding (e.g.,-prevent flashover);

(b) A reduct ion in tile threat to occupants, where the primary objective is to minimize the loss of life;

(c) A reduct ion in a fire-related characteristic such as heat release rate, fire growth rate, or spread to adjacent objects.

5-1.1.2 Fire Suppress ion. Fire suppress ion is the sharp reduct ion in the hea t release rate of a fire and tile prevent ion of its-regrowth by a sufficient application of water mist.

5-1.1.3 Fire Ext inguishment . Fire ex t ingu i shmen t is the complete suppress ion of a fire until there are no bu rn ing combust ib les_

5-2 Application Parameters. Design considerat ions shall address both c o m p a r t m e n t variables and tlre hazard classification.

5-2.1 Compar tmen t Variables. Comiaar tment variables shall include both tile geometry of tile c o m p a r t m t n t and the ventilation condit ions in file compar tment .

5-2.1.1 Compa r t men t Geometry. The c o m p a r t m e n t geometry (floor area, c o m p a r t m e n t volume, ceiling height , and-aspect ratio) shall be considered when des igning sucffparaTmeters as fiozzle locations, system flow rate, and total water use needs of the system.

5-2.1.2 Ventilation. Ventilation considerat ions shall include both natural and forced ventilation parameters .

5-2.1.2.1" Natural Ventilation. The number , size, and location of the openings in the space (e.g., door, windows) shall be addressed in the design a-rid installation o f the system. In some cases, special

ecautions are necessary to minimize the effects of these openings. ese precaut ions include, but are no t l imited to, automat ic door

closures and water mist curtains.

5-2.1.2.2 Forced Ventilation. The magni tude of tile forced ventilation in the c o m p a r t m e n t shall be addressed in the design and installation of the wate-r mist system. In some cases, considerati~ on shall be given to shut t ing down the forced ventilation prior to mist system activation.

5-2.2 Fire Hazard Classification. The fire hazard shall be classified by both the fuel type and combust ible loading.

5-2.2.1 Combust ib le Loading. A fire hazard analysis shall be conduc ted to de t e rmine boffi the design parameters of the water mist system and the type of detect ion/~ct lvat ion scheme employed by the system. The system shall be based on the fuel type, combustible loading, and anticipated fire growth rate as well as tile desired fire-fighting performanc-e objective-s.

678

5-2.2.2 Fuel Type. Overall fire hazard is directly related to the type and quanti ty of the fuel present in a space. The ease of igni t ion/- re igmtion of the fuel, the fire growth rate, and the difficulty of acl~ieving control, suppression, ext inguishment , or any combinat ion thereof, ghall be conf idered when selbcting or des igning a water mist system.

5-2.2.2.1 Class A Fires. Fuel loading and configurat ion shall be considered when selecting/designin-g a system to protect a space or area containing Class A rnaterial-s. If-fire ex t ingu i shmen t is desired, considerat ion shall be given to the potential four deep-seated fires as well as to the potential for smolder ing fires.

5-2.2.2.2 Class B Fires. The hazard associated with Class B fires is related primarily to the fuel loading, fuel configuration, flashpoint, and bu rn ing rate of the fuel. Preburn t ime also affects tile overall characteristics of the fire. Class B fires are g roupe d into two categories: two-dimensional pool fires and- three-dimensional spray and i -unning fuel fires. The parameters associated with each category are as follows:

(a) Class B two-dimensional fires:

1. Fuel loading and configuration;

2. Fuel flashpoint;

3. Preburn time pool/spil l size.

(b) Class B three-dimensional fires:

1. Fuel loading and configuration;

2. Fuel fiashpoint;

3. Preburn time;

4. C a s c a d e / r u n n i n g fuel fires;

5. Fuel flow rate;

6. Fire configuration;

7. Spray fires;

8. Fuel line pressure;

9. Fuel spray angle;

10. Fuel spray orientation;

11. Reignition sources.

When des igning and installing water mist systems to protect Class B hazards, the parameters specified in 5-2.2.2.2(a) and (b) shall be considered.

5-2.2.2.5 Class C Fires. The electrical conductivity of water mist in addit ion to the electrical potential in and a r o u n d the a rea / e q u i p m e n t to be protected shall be addressed when considering apphcat ions where the primary fire threa t is f rom Class C fires.

5-2.2.2.4 Combinat ion Fires. Combinat ions in fuel loadings an d hazards shall be addressed.

5-2.3 Fire Location. The location of the fuel in the space shall be considered when se lec t ing /des ign ing a water mist system. Some of the locations of concern include: -

(a) Fuel located at h igher elevations in the space;

(b) Fuel located in close proximity to vent openings;

(c) Fuel located in the corners of the space; and

(d) Fuel stacked against walls.

5-2.4 Obstructions and Shielding. Water mist nozzles shall be posi t ioned to distribute mist to all locations in the area or a round i:he object being protected. The presence of obstructions an d the potential for shielding of mist ing spray pat terns shall be evaluated to ensure that the system per formance is no t affected. 5-3 Listing Testing. Tests shall be conducted as part of the nozzle or system listing to address tile c o m p a r t m e n t geometry, fire hazard, and performance objectives of tile applicatI~on specified in the listing.

5-3.1 Applicability. Tests shall be des igned to replicate mos t or all of the a-pplication ~aramete r s associatgd with a given installation. Any variations in these parameters shall be subst i tuted us ing the worst case conditions. The listing of the system hardware shall be consistent with the in t ended system application.

NFPA 750 - - A96 ROP

5-3.2 Adequacy of Testing. Tests shall be designed and conducted to stress the system in order to de termine the working limits/ parameters of the system and to incorporate adequate severity to minimize the effects of test parameter variations.

5-3.3* Results. The results documented in the listing testing shall identify the working l imits/parameters of the system, the fire hazard, and the range of compar tment parameters. (See A-5-3. 3.)

Chapter 6 Calculations

6-1 General. System flow calculation procedures for water mist systems shall be in accordance with Section 6-2.

ExcePtion No. 1: Hydraulic calculations for systems with no additives and with'working pressures not exceeding 17Ypsi (12 bars) shall be permitted to be performed using the .method prowded in Section 6-3.

Excaption No. 2: Calculations for piping carrying atomizing media in twin fluid systems shall be perfornwc[ in aceorEanee'with Section 6-4.

6-1.1" Where any modification is made that alters the system flow characteristics of an existing engineered water mist system, system flow calculations shall be furnished indicating the previous design, volume, and pressure at points of connection, and adequate calculations also shall be provided to indicate the effect on existing systems.

6-1.2 Pro-engineered systems shall not be modified outside the limits of the lisdng.

6-2 Darcy-Weisbach Calculation Method (Intermediate and High Pressure Systems).

6-2.1 Pipe friction losses shall be de te rmined on the basis of the following formula:

0 .000216 f L p Q 2 Ap - d5

where: Ap = Friction loss (psi)

L = Length of pipe fit)

f= Friction factor (psi/ft)

13 = Weight density of fluid (Ib/f t 3)

Q = Flow (gpm)

d = Internal pipe diameter (in.).

A L p w 2 For SI units: Ap = 2 d s

where: Ap = Friction loss (bars)

= Frictional resistance coefficient

L = Length of pipe (m)

d s = Inside diameter (ram)

p = Density of the liquid (kg /m 3)

w = Stream velocity (m/ra in) .

6-2.2 FiR;tire 6-2.2 shall be used to determine the value of the friction ~'actor, f, in the equation in 6-2.1, where the Reynolds number, Re, is de te rmined as:

Re = 5 0 . 6 0 ~ d ~

where p. = absolute (dynamic) viscosity (cP).

For SI units: L K / d s 2.51

7 . f f = - 0 . 8 6 In 3.7 Re~]~

where k = roughness of the surface (m).

10 5 2 3 4 5 6 8 10 4 2 3 4 5 6 8 IO s 2 3 4 S 6 8 10 6

REYNOLDS NUMBER (R)

Figure 6-2.2 Moody diagram.

679

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N F P A 7 5 0 - - A 9 6 R O P

6-2.3 The following values of roughness, ~, shall be used where determining e / d for use with Figure 6-2.2:

Design Value of Pipe Material (it)

Stainless steel 0.00015

Copper nickel 0.000005

Copper 0.000005

6-2.4 Minimum and maximum operating pressure at each nozzle shall be within the listed operating range.

6-2.5 System piping shall be hydraulically designed to deliver the water flow reqmrements in accordance with the manufacturer's listing and the provisions of Chapter 5.

6-3 Hazen-Williams Calculation Method (Low Pressure Systems).

6-3.1 Hydraulic calculations for water mist systems with working pressures not exceeding 175 psi (12 bar~) shall be permitted to be performed using the Hazen-Williams calculation method.

6-3.2 Friction Loss Formula. Friction losses for water-filled pipe shall be determined on the basis of the Hazen-Williams formula.

4 .52 Q L 8 5

P f - C1.85d4.87

where: P~ Frictional resistance (psi/ft of pipe)

Q = Gpm flowing

d = Actual internal diameter of pipe (in.)

C = Friction loss coefficient.

For SI units:

P m = 6.05 Q m l ' 8 5

C1-85dm4.87

where:

x 10 5

Pm = Frictional resistance (bars/m of pipe)

Qm = Flow (L/min)

d m = Actual internal diameter of pipe (mm)

C = Friction loss coefficient.

6-3.3 Velocity Pressure Formula. Velocity pressure for water-filled pipe shall be determined on the basis of the formula

0.001123 Q2 Pv = D4

where: Pv = Velocity pressure (psi)

Q= Flow (gpm)

D = Inside diameter (in.).

For SI units:

Q2

Pv = 5.61(10) - 7 D4

where:

Pv = Velocity pressure (bars)

Q = Flow (L/rain)

D = Inside diameter (mm).

6-3.4 Normal Pressure Formula. Normal pressure, Pn, shall be determined on the basis of the formula

Pn = Pt - Pv

where: Pn = Normal pressure

Pt = Total pressure [psi (bars) ]

Pv = Velocity pressure [psi (bars)].

6-3.5 Hydraulic Junction Points. Pressures at hydraulic junction points shall balance within 0.5 psi (0.03 bar). The highest pressure at the junction point, and the total flows as adjusted, shall be used in the calculations.

6-3.6 Equivalent Pipe Lengths of Valves and Fittings.

6-3.6.1 Table 6-3.6.1 shall be used to determine the equivalent length of pipe for fittings and devices, unless the manufacturer's test data. indicate, that. other factors are appropriate. For. saddle-type fittings hawng friction loss greater than that shown ,n Table 6-3.6.1, the increased friction loss shall be included in hydraulic calculations. For internal pipe diameters that differ from copper tubing, the equivalent feet shown in Table 6-3.6.1 shall be multipliedby a factor derived from the following formula:

Actual inside d iamete r ] 4.87

Schedule 40 steel p i p e ' Factor

inside d iamete r

The factor thus obtained shall be modified further in accordance with Table 6-3.6.2 shown on the following page.

6-3.6.2 Table 6-3.6.1 shall be used with Hazen-Williams only where C=120. For other values of C, the values in Table 6-3.6.1 shall be multiplied by the factors in Table 6-3.6.2.

Table 6-3.6.2 C Value Multiplier

Value of C 130 140 150 Multiplying Factor 1.16 1.33 1.51

NOTE: The multiplying factor is based upon the friction loss through the fitting being independent of the C factor available to the piping.

6-5.6.3 Specific friction loss values or equivalent pipe lengths for special valves, strainers, and other devices shall be made available to the authority having jurisdiction.

6-3.6.4 Pipe friction loss shall be calculated in accordance with the Hazen-Williams formula C values from Table 6-3.6.4.

Table 6-3.6.4 Hazen-W'flliams C Values

Pipe or Tube C Value 1

Plastic (listed per 2-3.2.3 or 2-3.3.2) - - all types

Copper tube or stainless steel

150

150

1Th e au th ority having jurisdiction is permitted to consider other C values.

6-4 Pneumatic Calculation Procedures for Atomizing Media in Twin Fluid Systems.

(This section is extracted from the manufacturer's specifications or other sources, or both. Calculations are balanced at each nozzle. To come from ROC.)

680 .

Table 6-$.6.1 Equivalent Length of Pipe for Copper Fittings and Valves 1

I rabows I Tees I Valves

Diameter I 45 Degrees I 90 Degrees I Long Radius I Flow through Cock Branch Run Pattern

in. mm ft m ft m ft m ~ ~ ~ ~ ~ ~

IE llox:i i i iolJ i ! i ---- Ia_ F_~II i L m i n ~ 9 1 ~ n ~ , ~ ~ i ii~i ~ 1 ~y~i:l i:~,i I~A~:I ~ i ~i:ioi[,~ ~ ~ ~ i ~

I ] , _ ~ w ~ L n I I m I i~ m~.~m I I ~ , l I I m m l I l l n l l l l l l l l l i i m i

1Due to the variations in design of swing check valves, the pipe equivalents indicated shall be considered to be average. NOTE: This table shall apply to copper tube or stainless steel pipe only.

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N F P A 7 5 0 1 A 9 6 R O P

C h a p t e r 7 W a t e r Supplies and Atomizing Media

7-1 General. Unless otherwise specified, the following requi rements shall apply to the water supplies, the a tomizing media, and any additives necessary for fire ext inguishing performance.

7-1.1 Every water mist system shall have at least one automat ic water supply.

7-1.2" Compressed gas or o ther a tomizing med ium, where used as part of a twin fluid water mist system, sha l l be automatically suppl ied in concur rence with the water.

7-2 Locat ion o f E q u i p m e n t .

7-2.1" Pressure source componen t s shall be located as close as possible to the hazard or hazards they protect, bu t shall be located outside of the protected area.

Exception: Where circumstances necessitate that the components be in the hazard area, an enclosure shaU be provided. Fire rating of the enelosure shall be appropriate to the hazard and acceptable to the authority having jurisdiction.

7-2.2 Gas and water containers and accessories shall be located and a r ranged so tha t inspection, testing, recharging, and o ther ma in tenance are facilitated and interrupt ion of protect ion is he ld to a min imum.

7-2.3 Gas and water containers shall be located where they cannot be subject to adverse a tmospher ic condi t ions or to potential damage due to mechanical , chemical, or o ther causes. Where potentially damag ing exposures exist, suitable enclosures or guards shall be provided.

7-3* Quantity. The quanti t ies of water and of atomizing media (if used) shall be at least sufficient for the largest single hazard or g roup of hazards to be protected simultaneously.

7-4* Durat ion . Automat ic supplies of water and of a tomizing media (if used) shall be adequate to supply the system for a m i n i m u m of 30 minutes .

Exception No. 1. For pre-engineered systems, the minimum duration shall be suffident for two complete discharges, as required by the listing and by Chapter 5.

Exception No. 2. Where the hazard has been evaluated by a fire protection engineer using standard methods of fire hazard analysis, the water supply duration shall be determined by the specified performance characteristics of the water mist ~stem. It shall be permitted for this method to result in water supply duration requirements greater than or less than those specified in Section 74.

7-5 R e s e r v e Suppl i e s .

7-5.1 Where a reserve supply is provided, it shall be connec ted to the system p i p i n g a t all times. I f a manua l changeover is necessary, the m e c h a n i s m shall be readily accessible f rom outside of the protected space.

7-5.2 Means shall be provided to prevent discharge of reserve supplies f rom open manifold connect ions when supplies are removed for servicing.

7-5.$ Where required, the reserve quanti t ies shall be as many mult iples of the primary supply as are considered necessary by the authori ty having jurisdiction.

7-6 W a t e r Suppl i e s .

7-6.1,* W a t e r Qual i ty ,

7-6.1.1 The water supply for a water mist system shall be taken f rom a potable water source.

7-6.1.2 Based on the smallest nozzle orifice d imens ion or the smallest water supply path used in the system, a stralner or filter shall be provided on the supply side of the nozzle in accordance with Table 7-6.1.2. The m a x i m u m filter rating or strainer mesh opening shall be 80 percent of the m i n i m u m orifice d imension.

Exception: Systems with self-contained stored water systems of under 53 gal (200 L) capacity shall not require nozzle strainers or filters.

7-6.1.3 Where a filter or strainer is provided at a water supply connect ion, it shall be installed downst ream (on the system side) of all p iping that is no t corrosion resistant.

7-6.1.4 Every in-line strainer shall be a r ranged with a c leanout port.

7-6.1.5 Filters shall be a r ranged to facilitate inspection, main tenance , and replacement .

7-6.2 P u m p s .

7-6.2.1 Centrifugal p u m p s shall be sized to supply the greatest d e m a n d at no t more than 140 percent of rated flow capacity.

7-6.2.2 Othe r p u m p s shall be sized to supply 110 percen t of system d e m a n d at the design pressure.

7-6.2.3 Pumps supplying water mist systems shall be automatically controlled and shall be of sufficient capacity to mee t the system demand .

7-6.2.4 Supervision. Pumps supplying water mist systems shall be supervised for the condit ions specified in 7-6.2.4.1 and 7-6.2.4.2.

7-6.2.4.1 Electric P u m p s .

(a) Pump runn ing ;

(b) Loss of power;

(c) Phase reversal.

7-6.2.4.2 Diesel-Driven P u m p s .

(a) Pump runn ing ;

(b) Power failure;

(c) Control ler no t in automatic position;

(d) Low oil pressure;

(e) High water temperature;

Table 7-6.1.2 Requirements for Nozz le Protection Protect ion Orif ice Size or Smallest Path Measures

< 50 lain 51-299 pm 300 lain - 800 [am >800 ~m (< 1.97 x 10 -3 in.) (2.01 x 10 -3 in. - 1.78 x I0 -2 in.) (1.18 x 10 -2 in. - 3.15 x I0 -2 in.) (> 3.15 x 10 -2 in.)

Filter or strainer at each water supply connection

Filter or strainer at each nozzle

Demineralized water

None required

X

and

X

and

X

X

and

X

X

OR

X

X

682

N F P A 750 - - A 9 6 R O P

(f) Failure to start/overcrank;

(g) Overspeed;

(h) Fuel level (set at 75 percent capacity).

7-6.3 Tanks.

7-6.3.1 Water tanks shall be arranged in accordance with NFPA 22, Standard for Water Tanks for Private Fire Protection.

7-6.3.2 Water tanks shall be supervised for the following conditions:

(a) Water level;

(b) Water temperature (for tanks located in unheated areas);

(c) Air pressure (for pressure tanks).

7-6.4 Storage Containers.

7-6.4.1 Storage containers and accessories shall be located and arranged to facilitate inspection, testing, recharging, and other maintenance. Interruption to protection shall be held to a minimum.

7-6.4.2 Storage conuxiners shall not be located where they are likely to be subject to severe weather conditions or to mechanical, chemical, or other damage.

7-6.4.3 Where excessive climatic or mechanical exposures are expected, suitable s:ffeguards or enclosures shall be provided.

7-6.4.4 Storage containers shall be mounted securely in accordance with the manufacturer's installation manual. This shall include mounting the container on the appropriate mounting surface.

, 7-6.5 Fire Department Connection. A fire department connection shall be provided on the discharge side of the pressure source components. The connection to the system shall be made on the upstream (supply) side of the system strainer or filter.

Exception No. 1: For systems with operating pressures in excess of 175 psi (12 bars), the connection shall be made on the suction side of the pressure source components.

Exception No. 2: Fire department cg, nnection ~ shall not be required for systems protecting less than 2000 f l ~ (200 rn'~ ).

Exception No. 3: Fire department connections shall not be required for systems with operating pressures in excess of 175 psi (12 bars) and supplied only by storage cylinders.

Exception No. 4: Fire department connections shall not be required for systems where the atomizing medium is essential for fire suppression.

7-7 Atomizing Media for Twin Fluid Systems

7-7.1 General.

7-7.1.1 Atomizing media essential to the production of water mist shall be taken from a dedicated source.

Exception: Where the fizcility has an air supply that meets or exceeds the requirements of a dedicated main and reserve air supply, both meeting the quality, quantity, pressure, and reliability requirements of the listing and the approval of the authori~ having jurisdiction. Plant air used as an atomizing mediurn for a water mist system shall be monitored by the fire control panel, with the Zow ah" alarm set at a point at least 50 percent above the availability of two f~ll system discharge requirements.

7-7.1.9 Atomizing media shall be supervised for high and low pressure.

7-7.1.3 Moisture content in the atomizing medium shall not exceed 25 ppm.

7-7.1.4 Regulators controlling the supply of water for the atomizing medium shall be listed for the intended purpose.

7-7.1.5 A check valve or other means shall be installed in the piping at the supply point to prevent the entrance of water into the atomizing medium.

7-7.1.6 Filters or other means to protect nozzles from obstructions shall be provided in accordance with Table 7-6.1.2.

7-7.2 Air Compressors.

7-7.2.1 Air compressors used as a dedicated source shall be listed for use on fire protection systems.

7-7.2.2 Compressors used as a dedicated supply shall be connected to a backup power supply.

7-8 Pressure Gauges A pressure gauge shall be provided for each water supply and each atomizing medium.

Chapter 8 Plans and Documentation

8-1 Working Plans.

8-1.1 Working plans shall be submitted for approval to the authority having jurisdiction before any equipment is installed or remodeled. Deviation from approved plans shall require permission of the authority having jurisdiction.

8-1.2 Working plans shall be drawn to specified scale on sheets of uniform size. Special symbols shall be defined and used to identify components of the water mist system clearly. The plans shall provide the following information that pertains to the design of the system:

(a) Name of owner and occupant.

(b) Location, including street address.

(c) Point of compass and symbol legend.

(d) Location and construction of protected enclosure walls and partitions.

(e) Location of fire walls.

(f) Enclosure cross section, with full height or schematic diagram, including location and construction of building floor/ceiling assemblies above and below, raised access floor, and suspended ceiling.

(g) Description of occupancies and hazards being protected, designating whether or not the enclosure is normally occupied.

(h) Description of exposures surrounding the enclosure.

(i) Description of water and gas storage containers used including make, internal volume, storage pressure, and nominal capacity expressed in units of mass or volume at standard conditions of temperature and pressure.

(j) Description of nozzles used including manufacturer, size, orifice port configuration, and orifice size or part number.

(k) Description of pipe and fittings used including material specifications, grade, and pressure rating.

(1) Description of wire or cable used including classification, gauge (AWG), shielding, number of strands in conductor, conductor material, mad color coding schedule. The segregation requirements of various system conductors shall be clearly indicated. The required method of making wire terminations shall be detailed.

(m) Description of the method of detector mounting.

(n) Equipment schedule or bill of materials for each piece of equipment or device indicating device name, manufacturer, model or part number, quantity, and description.

(o) Plan view of the protected area showing enclosure partitions (full and partial height); water distribution system including storage containers or pumps; gas distribution system including gas storage containers; piping; nozzles; type of pipe hangers and rigid pipe supports; detection, alarm, and control system including all devices; end-of-line device locations; location of controlled devices such as dampers and shutters; and location of instructional signage.

(p) Isometric view of the water mist distribution system showing the length and diameter of each pipe segment; node reference numbers relating to the flow calculations; fittings including reducers and strainers; orientation of tees; and nozzles including size, orifice port configuration, and flow rate.

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N F P A 7 5 0 - - A 9 6 R O P

(q) Seismic building joints, if any, showing where water mist distribution or supply piping crosses the joint; expected movement of the seismic joint; details of the piping arrangement; and flexible connectors used to accommodate seismic movement.

(r) The calculation of seismic loads if seismic restraint is required by the authority having jurisdiction.

(s) Scale drawing showing the layout of the annunciator panel graphics if required by the authority having jurisdiction.

(t) Details of each unique rigid pipe support configuration showing method of securement to the pipe and to the structure.

(u) Details of the method of container securement showing method of securement to the container and to the structure.

(v) Complete step-by-step description of the system sequence of operations including funct ioning of abort and maintenance switches, delay timers, and emergency power shutdown.

(w) Schematic diagrams and point-to-point wiring diagrams showing all circuit connections to the system control panels, detectors, system devices, controlled devices, external and add-on relays, and graphic annunciator panels.

(x) Schematic diagrams and point-to-point wiring diagrams of the system control panels.

(y) Complete calculations to de termine enclosure volume for the application of water mist.

• (z) Complete calculations to de termine the size of backup batteries; the me thod used to determine the number and location of audible and visual indicating devices; and number and location of detectors.

(aa) Details of any special features. The detail on the system shall include information and calculations on the me thod of producing water mist, including pneumatic calculations, if applicable; application density and drop size distribution; spray cone angle and diameter; container storage pressure and internal volume of the container; the location, type, and flow rate of each nozzle, including orifice size; the location, size, and equivalent lengths of pipe, fittings, and hose; the location and size of water storage; and the location, size, point of connection, and type of water supply.

Exception: Pre-en~neered systems.

8-2 Hydraulic Calculation Documentation.

8-2.1 Hydraulic calculations shall be prepared on form sheets that include a summary sheet, detailed work sheets, and a graph sheet.

Exception: Pre-eng~neered systems.

8-2.2 Summary Sheet. The summary sheet shall contain the following information:

(a) Date;

(b) Location;

(c) Name of owner and occupant;

(d) Building number or other identification;

(e) Description of hazard;

(f) Name and address of contractor or designer;

(g) Name of approving agency;,

(h) System design requirements, including:

1. Design area of water application or volume of space protected;

2. Minimum rate of water application (density);

3. Area per nozzle.

(i) Total water requirements as calculated;

(D Limitations (dimension, flow, and pressure) resulting from the use of automatic sprinkler systems or other water fire suppression systems.

684

8-2.3 Detailed Work Sheets. The detailed work sheets or computer printouts shall contain the following information:

(a) Sheet number;

(b) Nozzle description;

(c) Hydraulic reference points;

(d) Flow in gpm (L/min) ;

(e) Pipe size;

(f) Pipe lengths, center to center of fittings;

(g) Equivalent pipe lengths for fittings and devices;

(h) Friction loss in ps i / f t (bars /m) of pipe;

(i) Total friction loss between reference points;

(j) Elevation head in psi (bars) between reference points;

(k) Required pressure in psi (bars) at each reference point;

(1) Velocity pressure and normal pressure if included in calculations;

(m) System flushing locations;

(n) Notes to indicate starting points, reference other sheets, or clarify data shown;

(o) Diagram to accompany gridded system calculations to indicate flow quantities and directions for lines with water mist nozzles operating in the remote area;

(p) Other calculations necessary for design of the water mist system.

8-2.4 Graph Sheet. A graphic representat ion of the comple~ ^. hydraulic calculation shall be plotted on semilogarithmic (Q • ) graph paper and shall include the following:

(a) Water supply curve;

(b) Water mist system demand.

8-3 Pneumatic Calculation Documentation.

8-3.1 Pneumatic calculations shall be prepared on form sheets that include a summary sheet and detailed work sheets.

Exception: Pre-engineered systems.

8-$.2 Summary Sheet. The summary sheet shall contain the following information:

(a) Date;

(b) Location;

(c) Name of owner and occupant;

(d) Building number or other identification;

(e) Description O f hazard;

(f) Name and address of contractor or designer;

(g) Total gas volume required.

8-3.3 Detailed Work Sheets. The detailed work sheets or computer printouts shall contain the following information:

(a) Sheet number;

(b) Nozzle description;

(c) Pneumatic reference points;

(d) Flow rate;

(e) Pipe size;

(f) Pipe lengths;

N F P A 750 - - A96 R O P

(g) Total pressure loss be twten reference points;

(h) Required pressure in psi (bars) at each reference point;

(i) Notes to indicate starting points, reference other sheets, or clarify data shown.

8-4 Detection, Actuation, and Control Systems Documentation. After successful completion of acceptance tests satisfactory to the authority having jurisdiction, as-built installation d o c u m e n t a t o n shall be prepared and provided to the system owner or the owner's designated representative, includin~ as-built installation drawings, operation anti maintenance manuals, a written sequence of operation, and reports.

8-4.1 As-Built Installation Drawings. A set of as-built installation drawings, reproduci~ble and drawn to a scale specified on sheets of uniform size, shall provide the as-built configuration of detection, actuation, and control systems and shall include:

(a) The name of owner and occupant.

(b) The location, inc ludingst ree taddress .

(c) The plan view of the protected area showing all detector locations; end-of-line device locations; location of detector indicating lights if separate from the detectors; location of audible and visual indicating devices; location of control panels; location of manual release and abort switches; location of controlled devices such as dampers and shutters; location of maintenance and emergency power shutdown switches; and location of the annunciator panel.

(d) An equipment: schedule or bill of materials for each piece of equipment or device indicating the device name, manufacturer, model or part number , quantity, and description.

(e) A description of wire or cable used including classification, gauge (AWG), shielding, number of strands in conductor, conductor material, and color coding schedule. The segregation requirements of various system conductors shall be clearly indicated. The as-built me thod of making wire terminations shall be detailed.

(f) A scale drawing ~howing the graphics layout of all annunciator panels.

(g) Schematic diagrams and point-to-point wiring diagrams showing all circuit connections to the system control panels, detectors, system devices, controlled devices, external and add-on relays, and graphic annunciator panels.

(h) Schematic diagrams and point-to-point wiring diagrams of the system control panels.

(i) The size and type of backup batteries.

(j) The details of any special features.

84.2 Operation and Maintenance Manuals. Operat ion and maintenance manuals shall include operation and maintenance instructions for each piece of equipment or device of the as-built system.

8-4.3 Written Sequence of Operation. The written sequence of operation of the as-built system shall include a complete step-by-step description of the functioning of abort and maintenance switches, delay timers, and emergency power shutdown features.

8-4.4 Reports. Reports shall include inspection, testing, and maintenance reports.

Chapter 9 System Acceptance

9-1 Approval o f Water Mist Systems. The completed system shall be reviewed and tested by qualified personnel to meet the approval of the authority having jurisdiction. These personnel shall confirm that listed equipmetat and devices have been used in the system where required by this standard. To de termine that the system has been properly installed and functions as specified, the installing contractor shall:

(a) Notify the authority having jurisdiction and the owner's representative of the time and date testing is to be performed.

(b) Perform all required acceptance tests.

685

9-2* Acceptance Requirements.

9-2.1 Flushing or Cleaning of Piping.

9-2.1.1 Water Supply Connection. Where systems are connected to municipal or private water supplies, underground mains and lead-in connections to water mist system piping shall be flushed completely before c o n n e c t o n is i~ade to water mist piping. The flushing operation shall be cont inued for a sufficient time to ensure thorough cleaning. The minimum rate of flow shall be one of the following, whichever is greater:

(a) The hydraulically calculated water demand rate of the system; or

(b) The maximum flow rate available to the system under fire conditions.

9-2.1.2 System Pipe or Tube. Each pipe or tube section shall be cleaned internally after preparation and before assembly in accordance with the manufacturer 's installation manual. The piping network shall be free of particulate matter and oil residue before installation of nozzles or discharge devices.

9-2.2 Hydrostatic Tests.

9-2.2.1 General.

9-2.2.1.1 The test pressure shall be read from a gauge located at the low elevation point of the system or port ion being tested.

9-2.2.1.2. Water used for testing shall be filtered or strained to remove all solids of a size sufficient to obstruct the water mist nozzles.

9-2.2.1.3 Additives, corrosive chemicals such as sodium silicate or derivatives of sodium silicate, brine, or other chemicals shall not be used while hydrostatically testing systems or for s topping leaks.

9-2.2.1.4 Test blanks shall have painted lugs protruding in such a way as to clearly indicate their presence. The test blanks shall be numbered, and the installing contractor shall have a recordkeeping method to ensure their removal after work is completed.

9-2.2.2 Low Pressure System. All interior piping and attached appurtenances subjected to system working pressure shall be hydrostatically tested at 200 psi (13.8 bars) and shall maintain that pressure without loss for 2 hours. Loss shall be de te rmined by a drop in gauge pressure or visible leakage.

Exception No. 1: Portions of systems normally subjected to working pressures in excess of l5O psi (10.4 bars) shall be tested'as described above at a pressure of 5O psi (3.5 bars) in excess of normal working pressur~

Exception No. 2: Where cold weather does not allow testing with water, an interim air test shall be conducted as described in 9-2.3.

9-2.2.3 Intermediate and High Pressure Systems. All interior piping and attached appurtenances subjected to system pressure shall be hydrostatically tested to 150 percent of the rated working pressure and shall maintain that pressure without loss for 2 hours. Loss shall be de te rmined by a drop in gauge pressure or visible leakage.

9-2.3 Air Tests. For dry and preaction systems, an air pressure leakage test at 40 psi (2.8 bars) shall be conducted for 24 hours in addition to the standard hydrostatic test. Any leakage that results in a loss of pressure in excess of 1 1 /2 psi (0.1 bars) during the 24 hours shall be corrected.

9-2.4 Review of Components.

9-2.4.1 Review of Mechanical Components.

9-2.4.1.1 The piping system shall be inspected to determine that it is in compliance with the design and installation documents and hydraulic calculations.

9-2.4.1.2 Nozzles and pipe size shall be in accordance with system drawings. The means of pipe size reduction and the attitudes of tees shall be checked for conformance to the design.

9-2.4.1.3 Piping joints, discharge nozzles, and piping supports shall be fastened securely to prevent unacceptable vertical or lateral movement during discharge. Discharge nozzles shall be installed in such a manner that piping cannot become detached during discharge.

N F P A 750 - - A 9 6 R O P

9-2.4.1.4 The discharge nozzle shall be or iented in such a m a n n e r that op t imum water mist applicat ion can be effected.

9-2.4.1.5 The discharge nozzles, piping, and m o u n t i n g brackets shall be installed in such a m a n n e r that they do not potentially cause injury to personnel .

9-2.4.1.6 All water and gas storage containers shall be located properly in accordance with an approved set of system drawings.

9-2.4.1.7 All containers and m o u n t i n g brackets shall be fas tened securely in accordance with the manufac tu re r ' s requirements .

9-2.4.2 Review of Electrical Components.

9-2.4.2.1 All wiring systems shall be checked for proper installation in condui t and in compliance with the approved drawings. It shall be conf i rmed that AC wiring a n d DC wiring are no t combined in a c o m m o n condui t or raceway unless properly shielded and g rounded .

9-2.4.2.2 All field circuits shall be conf i rmed to be free of g r o u n d faults and shor t circuits. Where measur ing field circuitry, all electronic componen t s (such as smoke and f lame detectors or special electronic e q u i p m e n t for o ther detectors or their m o u n t i n g bases) shall be removed and j u m p e r s shall be installed properly to prevent the possibility of damage within these devices. C o m p o n e n t s shall be replaced after measur ing.

9-2.4.2.3 The detect ion devices shall be checked for proper type and location as specified on the system drawings.

9-2.4.2.4 The detectors shall be installed in a professional m a n n e r and in accordance with technical data regarding their installation. NFPA 72, NationalFireAlarm Code, shall be referenced for installation requirements . In Canada, C A N / U L C $524-M86, Standard for the Installation of Fire Ala ,n Systems, and C A N / U L C $529-M87, Smoke Detectors for Fire Alarm Systems, shall be referenced.

9-2.4.2.5 Manual pull stations shall be conf i rmed as readily accessible, accurately identified, and properly protected to prevent damage.

9-2.4.2.6 For systems using abor t switches, the switches shall be conf i rmed to be of the d e a d m a n type that necessitates cons tant manua l pressure, properly installed, readily accessible within the hazard area, and clearly identified. Switches that remain in the abort position when released shall no t be permi t ted for this purpose. Verification tha t normal and manua l emergency control overrides the abor t funct ion shall be made.

9-2.4.2.7 Polarity shall have been observed on all polarized alarm devices and auxiliary r e l ay s .

9-2.4.2.8 All end-of-line resistors shall have been installed across the detection and alarm bell circuits where required.

9-2.4.2.9 The control uni t shall be checked for proper installation and ready accessibility.

9-2.4.2.10" All wiring systems shall be checked for proper grounding and shielding. It shall be verified tha t the water mist system branch piping has no t been used as an electrical ground.

9-2.5 Preliminary Functional Tests.

9-2.5.1 If the system is connec ted to an alarm receiving office, the alarm receiving office shall be notified tha t the fire system test is to be conduc ted and tha t an emergency response by the fire depart- men t is no t desired. All conce rned personnel at the end-user 's facility shall be notified that a test is to be conduc ted and shall be instructed as to the sequence o f operation.

9-2.5.2 Each water mist release mechan i sm shall be disabled so that activation of the release circuit does no t release water mist. The release circuit shall be reconnec ted with a funct ional device in lieu of each water mist release mechanism. For electricaUyactuated release mechanisms , these devices can include 24-volt lamps, flash bulbs, or circuit breakers. For pneumat icai ly actuated release mechanisms , these de~ices can include pressure gauges. The manufac tu re r ' s installation manua l shall be referenced for recom- m e n d e d procedures and test methods .

9-2.5.3 Each detector shall be checked for proper response.

9-2.5.4 All auxiliary funct ions such as alarm sound ing or displaying devices, remote annuncia tors , a i r-handl ing shutdown, an d power shutdown shall be checked for proper operat ion in accordance with system requi rements and design specifications.

9-2.5.5 Manual pull stations shall be checked to confirm that they override abor t switches.

9-2.5.6 All supervised circuits shall be checked for proper trouble response.

9-2.6 System Operational Tests.

9-2.6.1 Where practicable, full flow tests of the system piping using water shall be made as a means of checking the nozzle layout, discharge pattern, and any obstructions and to de te rmine the relationship between design criteria and actual per formance and to ensure against clogging of the smaller piping a n d nozzles by foreign mat ter carried by the water.

9-2.6.2 Where practicable, the m a x i m u m n u m b e r of systems that are expected to operate in case of fire shall be in full operat ion s imultaneously when checking the adequacy and condit ion of the water supply.

9-2.6.3 All operat ing parts of the system shall be tested fully to ensure they funct ion as in tended. It shall be verified that all devices funct ion properly and tha t they are properly sequenced.

9-2.6.4 After flow testing, all filters and strainers shall be inspected, and cleaned or replaced, as necessary.

Chapter 10 System Maintenance

10-1 Responsibility of the Owner or Occupant.

10-1.1 The responsibility for properly main ta in ing a water mis t f i re protect ion system shall be the obligation of the property owner. By means of periodic inspection, tests, and main tenance , the equip- m e n t sha l / be shown to be in good opera t ing condition, or any defects or impa i rments will be revealed.

10-1.2 Inspection, testing, and ma in tenance activities shall be imp lemen ted in accordance with procedures mee t ing or exceeding those established in this d o c u m e n t and in accordance with the manufac tu re r ' s instructions. These tasks shall be pe r fo rmed by personnel who have developed competence th rough training an d experience.

10-1.3 The owner or occupan t shall notify the authori ty having jurisdiction, the fire d e p a r t m e n t (if required) , and the alarm receiving facility before shut t ing down a system or its supply. The notification shall include the purpose for the shutdown, the system or c o m p o n e n t involved, and the es t imated t ime needed. The authori ty having jurisdiction, the fire depar tment , and the alarm receiving facility shall be notified when the system, supply, or c o m p o n e n t is r e tu rned to service.

10-1.4 The owner or occupan t shall prompt ly correct or repair deficiencies, damaged parts, or impai rments f ound while perform- ing the inspection, test, and ma in tenance requ i rements of this s tandard. Corrections and repairs shall be pe r fo rmed by qualified ma in t enance personnel or a qualified contractor.

10-1.5 The owner or occupan t shall give special a t tent ion to factors that migh t alter the requ i rements for a con t inued satisfactory or acceptable installation. Such factors shall include, bu t shall no t be l imited to:

(a) Occupancy changes;

(b) Process or material changes;

(c) Structural revisions such as relocated walls, added horizontal or vertical obstructions, or ventilation changes;

(d) Removal of hea t ing systems in spaces with piping subject to freezing.

10-1.6 Where changes in the occupancy, hazard, water supply, storage a r rangement , structural modification, or o ther condi t ion that affects the installation criteria of the system are identified, the owner or occupant shall prompt ly take steps to e~aluate the adequacy of the installed system to protect the hazard in question,

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such as contact ing a qualified contractor, consultant, or engineer . Where the evaluation reve,'ds a deficiency, the owner shall nodfy the insurance underwriter , the authori ty having jurisdict ion, and the local fire depar tment .

10-1.7 Where a water mist system is r e tu rned to service following an impairment , it shall be verified that it is working properly. Chapter 9 shall be referenced to provide guidance on the type of inspect ion or test, or both, that is required.

10-2 Inspect ion and Testing. All componen t s and systems shall be inspected and tested to verify tha t they funct ion as in tended. The f requency of inspect ions and tests shall be in accordance with Tables 10-2(a) and (b). Following tests of componen t s or port ions of water mist systeuts that require valves to be opened or closed, the system shall be r e tu rned to service, with verification that all valves are restored to their normal operat ing position. Plugs or caps for auxiliary drains or test valves shall be replaced.

10-2.1 Test results shall be compared with those of the original acceptance test (if available) and with the most recent test results.

10-2.2 Inspection and testing requ i rements for each c o m p o n e n t are provided in Tables 10-2(a) and (b).

10-2.3 Specialized equ ipm en t required for testing shall be in accordance with the r~hanufacturer's specifications.

Table 10-2(a) Inspection Frequencies Item Activity F r e q u e n c y Reference

/paragraph) Air pressure cylinders t Check pressure Monthly

(where provided) and indicator disk

Water tank 1 Check water level Monthly

System operating components Inspect Monthly (unsupervmed)

System operating components Inspect Quarterly (supervised)

Alarm and supervisory devices Inspect and test Quarterly (random sample)

Batteries, control panel, Inspect Semiannu initiating devices, intelface ally equipment

Control equipment, fiber optic Inspect Annually cable connections

Piping, fittings, hangers, nobles, Inspect Annually flexible tubing

System filters Inspect Annuall~ 1 Where the air pressure and water levels are supervtsed by an automatic fire detection and alarm panel, the frequency of inspection shall be linked to that of the ,alarm and control panel.

10-3 Maintenance.

10-3.1 Maintenance shall be pe r fo rmed to keep the system equ ipmen t operable or to make repairs. As-built system installation drawings, original acceptance test records, and device manufac tu re r ' s ma in tenance bulletins shall be re ta ined to assist in the proper care of the system and its components .

10-3.2, Preventive ma in tenance includes, but is no t l imited to, lubricating control vane stems, adjusting packing glands on valves and pumps, bleeding moisture and condensation from air compressors and air lines, and cleaning strainers. Scheduled maintenance shall be performed as outlined in Table 10-3.2.

10-3.3 Corrective maintenance includes, but is not limited to, replacing loaded, co,'roded, or painted nozzles, replacing missing or loose pipe hangers, cleaning clogged fire pumps, replacing valve seats and gaskets, and restoring heat in areas subject to freezing temperatures where water-filled piping is installed.

10-3.4 Emergency maintenance includes, but is not limited to, repairs due to piping failures caused by freezing or impact damage, repairs to broken water mains, and replacing frozen or fused nozzles, defective electric power, or alarm and detection system wiring.

Item Table 10-2{b) Testing Frequencies

Activity Frequency Reference (paragraph)

Pumps

Air source for twin fluid systems 1

Control equipment (functions, fuses, interfaces, primary power, remote alarm)

System strainers and filters

Remote alarm annunciation

Pumps

Batteries

Detectors (other than single use or self- testing)

Release mechanisms (manual and automatic)

Control unit/pLC (includes lamps, LEDs)

Section valve

Water

Battery in PLC

High pressure cylinders 1

Open head and nonprcssurized systems

High pressure cylinders 1

Automatic nozzles

Operation test Weekly (no flow)

Test Weekly

Test Quarterly

Flow test Quarterly

Test Sem tannually

Function test Semiannually (full flow)

Test Semiannually

Test Annually

Test Annually

Test Annually

Function test Annually

Analysis of Annually content~ Test Annually

Pressure test (with Annually discharge, if possible)

Flow test A.nnually

Hydrostatic test 5-12 years

Test (random 20 years sample)

I Where the air pressure and water levels are supervised by an automatic fire detection and alarm panel, the frequency of inspection shall be linked to that of the alarm and control panel.

Table 10-3.2 Maintenance Frequencies

I t e m

Water

System

Water tank

Strainers

Filters

Activity

Analysis of contents

Flushing

Clean

Cleon or replace

Replace

Frequency

Annually

Annually

Annually

Quarterly or as needed

Annually

Reference (para~vaph)

10-3.5 Specific ma in t enance activities, where applicable to the type of water mist system, shall be per formed in accordance with the schedules in Table 10-3.2.

10-5.6 Replacement componen t s shall be in accordance with the manufac tu re r ' s specifications and the original system design. Spare componen t s shall be readily accessible and shall be s tored in a m a n n e r to prevent damage or contaminat ion.

10-3.7 After each system operation, a representative sample of operated water mist nozzles in the activated zone shall be inspected.

10-3.8 After each system operat ion due to fire, the system filters an d strainers shall be cleaned or replaced.

10-4 Training. All persons who might be expected to inspect, test, maintain, or operate water mist systems shall be t ra ined thoroughly in the funct ions they are expected to perform. Refresher t raining shall be provided as r e c o m m e n d e d by the manufac tu re r or by tile authori ty having jurisdiction.

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Chapter 11 Referenced Publications

11-1 The following documents or portions thereof are referenced within this s tandard and shall be considered part of the requirements of this document . The edition indicated for each reference is the current edition as of the date of the NFPA issuance of this document .

11-1.1 NFPA Publications. National Fire Protection Association, 1 Batterymarch Park, P.O. Box 9101, Quincy, MA 02269-9101.

NFPA 13, Standard for the Installation of Sprinkler Systems, 1994 edition.

NFPA 20, Stanclard for the Installation of Centrifugal Fire Pumps, 1993 edition.

NFPA 22, Standard for Water Tanks for Private Fire Protection, 1993 edition.

NFPA 70, National Electrical Code, 1996 editi on.

NFPA 72, NationaI Fire Alarm COde 1993 edition.

11-1.2 Other Publications.

11-1.2.1 ANSI Publications. American National Standards Institute, 11 West 42rid Street, NewYork, NY 10036.

ANSI B1.20.1, Pipe Threads, General Purpose (Inch), 1983.

ANSI B16.18, Cast Copper Alloy Solder Joint Pressure Fittings, 1984.

ANSI B16.22, Wrought Copper and Copper AUoy Solder Joint Pressure Fittings, 1989.

ANSI B31.1, Power Piping, 1992.

ANSI C-2, National Electrical Safety Code, 1993.

11-1.2.2 ASME Publications. American Society of Mechanical Engineers, 345 East 47th Street, NewYork, NY 10017.

ASME Boiler and Pressure Vessel Code, 1992.

ASME Code for Unfired Pressure Vessels for Petroleum Liquids and Gases,

11-1.2.3 ASTM Publications. American Society for Testing and Materials, 1916 Race Street, Philadelphia, PA 19103.

ASTM A269, Standard Specification for Seamless and Welded A ustenitie Stainless Steel Tubing for General Servi~ 1994.

ASTM A351/ASTM A351 M, Standard Specification for Castings, A ustenitic, Austenitic.Ferritie (Duplex) for Pressure-Containing Parts, 1994.

ASTM A403/ASTM A403M, Standard Specification for Wrought A ustenitie Stainless SteeI Piping Fittings, 1994.

ASTM A632, Standard Specification for Seamless and Welded A ustenitie Stainless Steel Tubing (Small-Diameter) for General Service, 1990. •

ASTM A774/ASTM A774M, Standard Specification for As-Welded Wrought Austenitie Stainless Steel Fittings for General Corrosive Service at Low and Moderate Temperatures, 1994.

A~STM A778, Standard Specification for Welded, Unannealed Austenitic Stainless Steel Tubular Products, 1990.

ASTM A789/ASTM A789M, Standard Specification for Seamless and Welded Ferritic/A ustenitic Stainless Steel Tubing for General Service 1994.

ASTM A815/ASTM A815M, Standard Specification for Wrought Fe~titic, Ferritic/A ustenitic, and Martensitic Stainless Steel Piping Fittings, 1994.

ASTM B32, Standard Specification for Solder Metal, 1994.

A~STM B75, Standard Specification for Seamless Copper Tube 1993.

ASTM B88, Standard Specification for Seamless Copper Water Tube 1993.

ASTM B251, Standard Specification for General R e q u i r ~ t s for Wrought ,Seamless Copper and Copper-Alloy Tube, 1993.

ASTM B813, Standard Specification for Liquid and Paste Fluxes for Soldering Applications of Copper and Copper AUoy Tube 1993.

11-1.2.4 AWS Publications. American Welding Society, Inc., 550 N.W. LeJeune Road, Maimi, FL 33126.

AWS A5.8, Specification for Filler Metals for Brazing and Braze Weldin~ 1992.

AWS D 10.9, Specification for Qualification of Welding Procedures and Welders for Piping and Tubin~ 1980.

11-1.2.5 IEE Publication. Institute of Elec~ical and Electronics Engineers, Inc., 445 Hose Lane, P.O. Box 1331, Piscataway, NJ 08855.

IEEE 45, Recommended Practice for Electric Installations on Shipboard, 1983.

11-1.2.6 ULC Publications. Underwriters Laboratories Canada, 7 Crouse Road, Scarborough, ON M1R 3A9.

CAN/ULC $524-M86, Standard for the lnstallation of Fire Alarm Systems.

CAN/ULC $529-M87, Smoke Detectors for Fire Alarm Systems.

11-1.2.7 U.S. Government Publications. Super intendent of Documents, U.S. Government Printing Office, Washington, DC 20401.

Title 29, Code of Federal Regulations.


11-1.2.8 U. S. Military Standards. Naval Publications and Forms Center, 5801 Tabor Avenue, Philadelphia, PA 19120.

MIL-STD-1310, Shipboard Bonding, Grounding, and Other Techniques for Electromagnetic Compatibility and Safety, December, 1992.

11-1.2.9 International Electromechanlcal Commission.

11-1.2.10 Transport Canada.

Appendix A Explanatory Material

This Appendix is not part of the requirements of this NFPA document but is included for informational purposes only.

A-I-I Other NFPA standards should be referenced for additional requirements relating to underg round or lead-in connections to water mist systems from municipal or private water supplies.

A-I-4.1 Approved. The National Fire Protection Association does not approve, inspect, or certify any installations, procedures, equipment, or materials; nor does it approve or evaluate testing laboratories. In determining the acceptability of installations, procedures, equipment, or materials, the authority having jurisdiction may base acceptance on compliance with NFPA or other appropriate standards. In the absence of such standards, said authority may require evidence of proper installation, procedure, or use. The authority having jurisdiction may also refer to the listings or labeling practices of an organization concerned with product evaluations that is in a position to determine compliance with appropriate standards for the current product ion of listed items.

A-14.1 Authority HavingJurisdiction. The phrase "authority having jurisdiction" is used in NFPA documents in a broad manner , since jurisdictions and approval agencies vary, as do their responsibilities. Wherepub l ic safety is primary, the authority having jurisdiction may be a federal, state, local, or other regional depar tment or individual such as a fire chief; fire marshal; chief of a fire prevention bureau, labor department , or health depar tment ; building official; electrical inspector; or others having statutory authority. For insurance purposes, an insurance inspection depar tment , rating bureau, or other insurance company representative may be the authority having jurisdiction. In many circumstances, the property owner or his or her designated agent assumes the role of the authority having jurisdiction; at government installations, the commanding officer or departmental official may be the authority having jurisdiction.

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N F P A 750 - - A96 R O P

A-14.1 Listed. The means for identifying listed ecjuipment may vary for each organization concerned with product evaluation, some of which do not recognize e q u i p m e n t as listed unless it is also labeled. The authori ty having jur isdic t ion shou ld utilize the system employed by the listing organization to identify a listed product.

A-14.1 Water Mist. This s tandard addresses tile use of fine water sprays for tile efficient control or ex t ingu i shment of fires us ing l imited volumes of water. Properly des igned water mist systems can be effective on both liquid fuel (Class B) and solid fuel (Class A) fires. Research indicates that droplets smaller than 400 microns are essential for ex t ingu i shment of Class B fires, while larger d rop sizes are effective for Class A combustibles, which also can benef i t f rom ex t ingu i shment by fuel wetting. For this reason, the definit ion of water mist in this s tandard includes sprays with Dr0.99 of up to 1000 microns.

The division of water mist into three classes allows description of die sprays in te rms more precise than "finer" or "coarser." The definit ion of water mist in this s tandard includes all water sprays for which 99 percent of the volume of die spray is conta ined in drops with diameters of less than 1000 microns (Dvn 99<1000). This definit ion is so broad that some impor tan t dii'f'erences in the qualities of sprays are disguised. It includes, for example, all watery sprays used in NFPA 15, Standard for WaterSprco Systems fo'r Fire Protection, sprays p roduced by s tandard sprinklers operat ing at h igh

~ ressure, and light mists suitable for g r eenhouse mist ing and HVAC umidificat ion systems. Each of these sprays migh t or migh t no t be

suitable for certain applications for water mist fire suppress ion systems.

The relationship between drop size distr ibution and die extinguishing capacity of a water mist is complex. In general, Class I and Class II sprays are successful at ext inguishing liquid fuel fires without agitation of liquid pool surfaces. Class III sprays have been used successfully on pool fires, however. Also, in general , it is difficult to ext inguish Class A combustibles with Class I mists, which migh t not achieve the fuel wetting necessary to penet ra te the char layer. Class A distribution is no t the only spray characteristic that de termines the ability of a spray to ext inguish a given fire. Factors such as enclosure effects, spray flux density, and spray m o m e n t u m combine to create condit ions dlat lead to ext inguishment .

By in t roducing a vocabulary to allow designers to dist inguish between coarser and f iner sprays, the relationship between drop size distribution, flux density, m o m e n t u m , and enclosure effects are better unders tood.

A-l-5 Applications o f Water Mist Systems. Water mist systems have been proven effective in controlling, suppressing, or ext inguishing many types of fires. Potential applications include:

(a) Gas j e t fires.

(b) Flammable and combustible liquids.

(c) Hazardous solids, inc luding fires involving plastic foam furnishings.

(d) Protection of aircraft occupants f rom an external pool fire long e n o u g h to provide t ime to escape.

(e) Ordinary (Class A) combust ible fires such as paper, wood, and textiles.

(f) Electrical hazards, such as t ransformers, switches, circuit breakers, a n d rotat ing equ ipment .

(g) Electronic equ ipment , including te lecommunica t ions equipment .

A-1-5.2.9 Water Reactive Materials. In special cases, where adequate safeguards have been provided, water mist systems for the protection of structures, equipment , or personnel in the presence of such materials as descr ibed in 1-5.2.2 may be permit ted.

A-l-6.1 Water mist is unlikely to present any significant hazard to personnel in most applications; however, direct i mp i ngemen t of the water mist could p resen t an eye hazard. Noise dur ing operat ion of the water mist systems could be a hazard to hearing. Water mist can reduce visibility and increase die t ime and difficulty in egress f rom an affected compar tment . Additionally, whipping or swinging of broken piping, tubing, and hoses could be a hazard, particularly for in termedia te and h igh pressure systems.

A-2-2.2.1 Marine vessels and buildings in locations subject to seismic activity migh t need restraints or bracing that differs f rom the manufac tu re r ' s installation manual .

A-2-2.2.2 I n d e p e n d e n t inspection and certification is r e c o m m e n d e d for gas and water containers.

A-2-3.1 It is impor tan t to select pipe or tube for water mist systems that exhibits minimal corrosion because of the potential for clogging of water mist nozzles.

A-2-3.3.2 Listed flexible connect ions may be permitted. Flexible connect ions for water mist installations should be kept as shor t as possible and should be protected against mechanical injury.

A-2-4.1 It is impor tan t to select fittings for water mist systems that exhibit minimal corrosion because of the potential for clogging of water mist nozzles.

A-2-4.2.2 Rubber-gasketed pipe fittings and couplings shou ld no t be installed where ambien t tempera tures can be expected to exceed 150°F (66°C) unless listed for such service, ff the manufac tu re r fur ther limits a given gasket compound , those r ecommenda t ions should be followed.

A-2-6.1 In recognit ion of the future value of scientifically based fire protect ion system engineer ing or design methods , bu t in considerat ion of the fact that the present water mist technology base is likely incomplete for general system design purposes, it is r e c o m m e n d e d that the nozzle listing agencies collect and repor t to the manufacturer tile following data for possible future use as required listing information:

(a) Cumulative volumetric distribution of water droplets to be measured at file centers on n ine 1-ft x 1-ft (0.305-m x 0.305-m) areas projecting outward f rom the central axis of the nozzle for a total of $ ft x $ ft (0.914 m x 0.914 m), in a quadrant , with the plane of tile measu remen t s to be or iented perpendicular to the central axis of the nozzle and posi t ioned 39.4 in. (1.0 m) be!ow the nozzle. The measuremen t s are to be made at the m i n i m u m and m a x i m u m rated operat ing pressures o f the nozzle, in accordance with ASTM E799, Standard Practice for Determining Data Criteria and Processing for Liquid Drop Size Analysis.

(b) Water discharge distribution in a plane 3.3 ft (1.0 m) below and perpendicular to die central axis of the nozzle us ing 1-ft x 1-ft (0.305-m x 0.305-m) collection pans. The water distr ibution measuremen t s are to be made at the m i n i m u m and m a x i m u m rated operat ing pressures of the nozzle and over an area sufficient to collect at least 90 percent of the water discharge.

(c) Profile of the nozzle spray envelope encompass ing at least 90 percent of the water discharge, measu red f rom the tip of the nozzle and ex tending over the effective range de t e rmined f rom the listing investigation. The profile of the nozzle spray envelope is to be provided at the m i n i m u m and m a x i m u m rated operat ing pressures of the nozzle as well as over the in t ended range of orientat ion angles, if in o ther than the vertically down orientation.

(d) Spray thrust force as measured in a plane perpendicular to the central axis of the nozzle, at a distance of 1 ft (0.305 m) below the nozzle and over an area sufficient to capture at least 90 percent of the water discharge. The measuremen t s are to be made at the m i n i m u m and m a x i m u m rated operat ing pressures of die nozzle.

A-2-10.2.1 Detectors installed at the m a x i m u m spacing as listed or approved for fire a larm use could result in excessive delay in water mist system actuation, especially where more than one detect ion device is required to be in alarm before automat ic actuat ion results.

A-4-6.1 Sizing p u m p s at 120 percent is arbitrary, bu t it is one way to ensure that the p u m p curve lies above the system operat ing point. It could be 110 percent or 150 percent , depend ing on die degree of conservatism desired. If the system strainer is likely to become partiaUy clogged dur ing operation, the overage shou ld be increased.

A-4-9.1.6 See ANSI C-2, NationalElectricalSafety Code;, NFPA 70, National Electrical Code;, and Title 29, Code of Federal Regulations, Part 1910, Subpart S.

A-4-9.3.1 Detectors installed at the m a x i m u m spacing as listed or approved for fire a larm use can result in excessive delay in agent release, especially where more than one detect ion device is required to be in a larm before automat ic actuat ion results.

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N F P A 7 5 0 - - A 9 6 R O P

A-5-2.1.2.1 Natural vent i la t ion/openings in the compar tment allow the hot gases layer (ceilingjet) to exhaust mist from the compartment, decreasing the extinguishing potential. The flow of gases into and out of the compar tment also alters the mixing characteristics of the system, which, in turn, might require the additional momen tum of the mist in order to overcome this alteration. Forced ventilation also significantly reduces the amount of mist in the compar tment as well as affects the mixing characteristics of the system.

Prior to or concurrent with the operation of the water mist system, consideration should be given to automatic closing of doors and dampers; shutdown of electrical equipment; and shutdown of HVAC equipment.

A-5-3.3 Results. The results of tile listing testing should identify the following:

(a) System Flow Rate (minimum and maximum).

1. Flow rate per unit area (if applicable) ;

2. Flow rate per unit volume (if applicable).

(b) System Operating Pressure (minimum and maximum).

1. Nozzle operating pressure range;

2. Pump/cyl inder operating pressure range;

3. Pump inlet and outlet pressure and flow rate requirements.

(c) GeneralWater Requirements.

1. Quanti ty/durat ion;

2. Quality;

3. Temperature.

(d) Nozzle Characteristics.

I. Type(s ) /model numbers;

2. Flow rate (minimum and maximum);

3. Operat ing pressure (minimum and maximum).

(e) Nozzle Spray Characteristics.

1. Spray angle;

2. Drop size distribution;

3. Momentum/velocity.

(f) Nozzle Installation Parameters.

1. Distance above floor (minimum and maximum);

2. Distance below ceiling (minimum and maximum);

3. Distance above hazard (minimum and maximum);

4. Nozzle spacing (minimum and maximum);

5. Orientation;

6. Minimum distance from walls;

7. Minimum distance from obstructions.

(g) Activation Device.

1. Type /mode l number;

2. Activation, temperature;

3. Activation, smoke obscuratiou.

(h) General Design Parameters.

1. Pipe Requirements.

a. Size;

b. Operating pressures/wall thicknesses.

2. Fittings.

a. Type;

b. Operating pressure.

3. Pumps.

a. Valves, fittings, and filters;

b. Power requirements;

c. Operat ing pressure and flow rates;

d. Water requirements.

4. Cylinders.

a. Valves and fittings;

b. Capacity;

c. Operating pressures.

A-6-1.1 The addition of piping and nozzles to an existing water mist system can render the system ineffective if it leads to reduced pressure and flow. The existing piping does not have to be increased in size to compensate for additional nozzles, provided the new work is calculated and the calculations include that portion of the existing system that is necessary to carry water or atomizing medium (if used) to the new work.

A-7-1.2 Although some water discharge might continue after the atomizing medium has been exhausted, it is not effective for fire suppression.

A-7-2.1 The fire rating of the enclosure protecting the pressure source components should be de termined by the occupancy hazard. Light and ordinary hazard occupancies require a 1-hour fire-rated enclosure; extra hazard occupancies require a 2-hour fire rating.

A-7-3 Some water mist systems protect single hazards or areas. Other system designs are based on multiple zones, with overlapping protection at the zone boundaries. It is also possible for one water mist system to provide local application protection for several individual hazards. Quantities ofwater and of atomizing media should be based on the most demanding location for the fire. For example, i f a fire could start at the intersection of four zones, the water supply and the atomizing medium (if used) should be able to supply all four zones simultaneously. If a water mist system protects several individual hazards that are located in close proximity, it might be necessary to design for simultaneous operation of multiple local application zones.

A-7-4 The 30-minute water supply requirement applies to water supply capacity and does not require that the system actually discharge for 30 minutes. This min imum duration should be provided for all water mist systems that are installed for life safety purposes or for structural protection. For water mist systems designed to protect equipment or other special hazards in unoccu- pied areas, Exception No. 1 allows the water supply duration to be de termined in accordance with Chapter 5. Exception No. 2 provides for performance-based design of water mist systems by qualified fire protection engineers. It should be noted that currently there is no generally accepted me thod for performance-based design of a water mist system.

A-7-6.1 Algae and bacteriological growth in stored water can clog the system by blocking the filters or strainers. Annual sampling or replacement of s toredwater is required by Table 10-2(b).

A-7-6.5 It is die intention of dais section to require a fire deparunent connect ion wherever it would be of benefit. Exception No. 2 provides for local area protection, where the fire depar tment could effectively respond with small hose streams or portable fire extinguishers. Exception No. 3 provides for systems where the pressures available from fire depar tment pumpers would not be adequate to supply the water mist system. Exception No. 4 exempts systems where the atomizing medium is essential for fire suppression and water alone would be of no benefit.

A-9-2 Acceptance Test Recommendations.

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(a) All tests shou ld be made by the contractor in the presence of an author ized inspector. W h e n an inspector is no t available, tests may be permi t ted t O be witnessed by the owner or owner 's representative.

(b) Before asking for final approval of the protective equipment , installing c'ompanies should furnish a written s ta tement to the effect tha t the work covered by its contract has been comple ted and all specified f lushing of unde rg round , lead-in, and system piping has been comple ted successfully, together with specified hydrostatic pressure tests.

A-9-2.4.2.10 Proper shielding and g r o u n d i n g is particularly impor tan t i fAC and DC wiring are combined in a c o m m o n condui t or raceway.

A-10-3.7 The representative sample shou ld include 10 percent of the water mist nozzles in the activated zone. If contaminat ion of filters or strainers is found on inspection, it is r e c o m m e n d e d that all nozzles within the ac t ivatedzone also be inspected.

Appendix B Research Summary

This Appendix is not part of the requirements of this NFPA document but is included for information al purposes only.

[Appendix B to come]

Appendix C Referenced Publications

G I The following documen t s or port ions the reof are referenced within this sandard for informational purposes only and thus are not considered part of the requ i rements of this document . The edit ion indicated for each reference is the cur ren t edition as of the date of the NFPA issuance of this document .

C-I.1 NFPA Publications. National Fire Protection Association, 1 Batterymarch Park, P.O. Box 9101, Quincy, MA 02269-9101.

NFPA 15, Standard for Water Spray Fixed Syster~ forFire Protection, 1990 edition.

NFPA 70, NationaIElectrical Code~ 1996 edition.

C-1.2 Othe r Publications.

C-1.2.1 ANSI Publication. Amer ican National Standards Institute, 11 West 42nd Street, NewYork, NY 10036.

ANSI C-2, National Electrical Safety Code, 1993.

C-1.2.2 ASTM Publications. American Society for Test ing and Materials, 1916 Race Street, Philadelphia, PA 19103.

ASTM E380, Standard Practice for Use of the International System of Units (SI) (the Modernized Metric System), 1993.

ASTM E799, Standard Practice for Determining Data Criteria and Processing for Liquid Drop Size Analysis, 1992.

C-1.2.3 CSA Publication. Canadian Standards Association.

CAN3-A234.1, Canadian Metric Practice Guide, 1979.

C-1.2.4 U.S. Government Publication. Super in t enden t of Docu- ments , U.S. Governmen t Print ing Office, Washington, DC 20401.


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