backflow prevention ashrae : american society of · pdf filebackflow prevention ashrae :...

Backflow Prevention

ASHRAE : American Society of

Heating, Refrigeration and Air-

Conditioning Engineers

Dubai, April 12th, 2016

2© 2015 Watts Water Technologies | Business Confidential & Proprietary Information

Watts Water overview

4/5/2016

Mission

To improve comfort, safety, and quality of life for people around the world through our expertise in a wide range of water technologies.

To be the best in the eyes of our associates, customers, and shareholders.

3© 2015 Watts Water Technologies | Business Confidential & Proprietary Information4/5/2016

Industry – Leading Brands

http://www.premierh2o.com/

http://www.premierh2o.com/

4© 2015 Watts Water Technologies | Business Confidential & Proprietary Information4/5/2016

SOCLA, Key numbers

4/5/2016

4, facilities (France and Germany)

74, M€ 2014 annual sales

300 employees

6 500 Customers worldwide


Presentation description

Backflow Prevention

This presentation serves as an introduction to further the understanding of the basic principles of backflow, various hydraulic systems used to protect the environment from contamination of potable water sources.

4/5/2016


After this presentation, you will be able to perform the following tasks:

• Explain the basic concepts and definitions of backflow

• Identify the risks and select the means to prevent pollution

• Understand basic types of hydraulics equipment that control backflow

Presentation description

4/5/2016


Scope of Standard BS EN1717

Introduction : what is a Back Siphonage – Pressure Backflow?

Determination of fluid categories which are – could be in contact

with potable water

Determination of installation characteristics

How to determine the protection units

Matrix of protection units

Protection devices to prevent pollution by backflow

Guide table

Presentation Outline

4/5/2016


Protection against pollution of potable water in water installations and

general requirements of devices to prevent pollution by backflow

4/5/2016

• BS EN1717 : 2000 - Scope

The standard deals with the means to be used to prevent the pollution of potable water inside premises and general requirements of protection devices to avoid pollution by backflow.

The hygiene protection specifications of this standard are applicable to all the standards for systems or appliances connected to the private supply system for water intended for human consumption

This standard specifies the minimum requirements for product standards of protection units.

The product standards are used to detail product specifications. In the absence of a product standard, this standard is used as a reference in order to draw up a specification for the products out of new development.


Backflow Prevention

4/5/2016

Water installations, due to their design or construction shall not be liable to generate pollution of public,

or private potable water supply system by residual matters, harmful water or any undesirable substance.


Analysis method of the risks at the point of use and choice of

protection

4/5/2016

A backflow of fluid in a potable water supply system can occur by:


Back siphonage: by a partial vacuum (drop in pressure) in potable water supply system (due for example to the bursting of pipe, the operation of a booster pump, excessive water demands in a part of the system, water taken for emergency use from a hydrant)

Back siphonage

4/5/2016


• Pressure backflow: by a back pressure originating in a non-potable system in which the pressure exceeds the pressure in the potable water system.

Pressure backflow

4/5/2016


Determination of fluid categories which are or could be in

contact with potable water

(1) The boarder between Cat 3 and Cat 4 is in principle LD50 = 200mg/kg body weight in reference to the EU Directive 93/21 EEC dated of April 27th, 1993

4/5/2016

Fluid representing a human health hazard due to the presence of microbiological or viral elements

Fluid representing some human health hazard due to the presence of one or more toxic or very toxic substances (1) or one or more radioactive, mutagenic or carcinogenic substances

Fluid representing some human health hazard due to presence of one or more harmful substances (1)

Fluid presenting no human health hazard. Fluid recognized as being fit for human being, including water taken from a potable water distribution system, which can have undergone a change in taste, odour, colour or temperature (heating or cooling)

Water to be used for human consumption coming directly from a potable water distribution system


Determination of the installation characteristics

4/5/2016

Pressure: define whether the protection point (existing or foreseen) or failing this,

the point of connection of the apparatus is subjected to atmospheric pressure (p=atm)

or to a pressure exceeding atmospheric pressure (p>atm)

The situation will be p=atm if the protection point (existing, foreseen) or, failing this,

the point of connection of the apparatus to the potable water network is located above the

Maximal operational level.

The situation will be p> atm if the protection point (existing, foreseen or, failing this,

the point of connection of the apparatus to the potable water network is located this maximal

operational level


How to determine the protection point?

4/5/2016

EA

RT3

EA

RT5

RT1a RT1c

RT1b – RT1d

EAEA

EAEA

EAEA

EA

RT1e

EA

NB

RT2

EA

NP

RT4

NE

NE

NE

Public potable water system

Private potable water system

NB: « branching » level

NP: « branch pipe » level

NE: « equipment » level

RT1: sanitary or alimentary purposeRT2: technical purpose (HVAC)RT3: fire protectionRT4: watering purpose (irrigation)RT5: specific purpose (industrial activities, Laundromat, car wash, …)


Matrix of the protection units appropriate to fluid

categories

4/5/2016

BP with controllable

reduced pressure

zone

―

BP with different non

controllable pressure

zones

― ―

3 4 5

CA

Fluid category 1 2

BA

Fluid category 1 2 3 4 5

Covers the risk Covers the risk only if p = atm ― does not cover the risk

Controllable

antipollution check

valve

― ― ―

Non controllable

antipollution check

valve

EA / EC

2

EB / ED

Fluid categoryFluid category 1 2 3 4 5 4 5

Only for certain domestic use

1 3


Hose union BP ― ―Hose union anti

vacuum valve― ―

HA

Fluid category

HD

Fluid category51 2 3 4 51 2 3 4



Antipollution check valve type EA

4/5/2016

Many water suppliers are now requiring containment at the water meter as a condition for the water user to receive or continue to receive the public water supply.


Hose Union Backflow Preventer type HA

4/5/2016

• Backsiphonage protection

• Non-continuous pressure

• Non-testable



4/5/2016

Normal Flow

FLOW



4/5/2016

Backsiphonage



4/5/2016


Backflow preventer with different non

controllable pressure zone type CA

4/5/2016

• Backsiphonage and backpressure protection

• Continuous pressure

• Non-testable

• Occasional water discharge




4/5/2016

Static Flow

60psi

57psi

52psi




4/5/2016

Normal Flow

60psi57psi

52psi

No more than 25psi of loss at rated flow

FLOW

60psi

56psi

51psi




4/5/2016

51psi60psi

Backsiphonage

52psi0psi


Backflow preventer non controllable type CA

4/5/2016

• Backsiphonage and backpressure protection


• Non-testable





4/5/2016

Protects against backpressure and back siphonage

SUPPLY

DRAIN

AIR GAP RETURN

WATTS AUTOMATIC FEED VALVE

BOILER

Residential Boiler Installation


Backflow Preventer with controllable reduced

pressure zones type BA

4/5/2016

51psi60psi 56psi

• Backsiphonage / backpressure protection



• Install above grade and allow space for normal testing and maintenance

• Typical Use:

• Everywhere – Check with local

Authorities




4/5/2016

51psi

60psi 56psi

Static Flow

60psi

57psi

52psi

PPT presentation/Animations DE-UK/Disconnecteur_BABM_Socla_HD.mp4




4/5/2016

51psi60psi 56psi

Dynamic Flow

FLOW

60psi

56psi

51psi



Backflow Preventer with controllable reducedpressure zones type BA

4/5/2016

51psi60psi 56psi

Backsiphonage

0psi 52psi



Guide table to determining the fluid category

from which protection is required

4/5/2016

51psi60psi 56psi



Water main protection is our daily concern

4/5/2016

51psi60psi 56psi


backflow prevention ashrae : american society of · pdf filebackflow prevention ashrae :...

Documents