* The conclusions and opinions in this memorandum are those of the author and do notnecessarily reflect those of the U.S. Environmental Protection Agency.

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON, D.C. 20460

OFFICE OF

SOLID WASTE AND EMERGENCY

RESPONSE

MEMORANDUM

DATE: August 29, 2002

SUBJECT: Stuyvesant High School Testing

– EPA validates use of sonication testing

– Brookfield CT school system using sonication

FROM: Cate Jenkins, Ph.D.*

jenkins.cate@epa.govWaste Identification Branch (Mail Code 5304 W)Hazardous Waste Identification Division

TO: Joel KupfermanNew York Environmental Law and Justice ProjectOther Concerned Parties and Responsible Officials

As per my communications with you and several of the parents, I have prepared thismemorandum validating both the use of and results from ultrasonication testing of carpets andother woven fabrics. It appears that officials responsible for the Stuyvesant High School clean upare trying to back away from proper testing after finding high asbestos levels with EPA’sultrasonication test.

EPA validates and relies on ultrasonication test results as way of showinghazards of ANY fabric contaminated by asbestos, and recommendsconsidering their replacement

EPA recently stated that results from the EPA ultrasonication method show high levels ofasbestos in carpet even after HEPA vacuuming and wet extraction cleaning. EPA further statesthat there is a potential problem with all asbestos contaminated fabric including upholsteredfurniture and curtains as well as carpet, based on ultrasonication tests.

In its fact sheet on all fabrics contaminated with asbestos after the World Trade Center collapse,EPA discusses two EPA studies which evaluated the effectiveness of cleaning asbestoscontaminated carpet. These two EPA studies used ultrasonication testing, not any microvacuumtest method, to determine asbestos levels before and after cleaning. (Note that on December 9,

- 2 -

2001, I widely distributed a memorandum discussing these same two EPA studies that showedthat neither HEPA vacuuming alone, nor HEPA vacuuming in conjunction with wet extraction,could effectively remove asbestos from carpets, and reiterated this data in subsequentmemoranda.)

Therefore, it is established that EPA is basing its conclusions as to the asbestos hazard fromcontaminated carpet and other woven fabrics, and the difficulty in removing asbestos from same, on ultrasonication test results, not the ASTM microvacuum test results.

Thus, any parties, such as the New York City Board of Education, making decisions for theasbestos testing and cleanup of the Stuyvesant High School auditorium, would be in oppositionto the position taken by EPA if they claim that results from ultrasonication testing of carpets andupholstered seats are irrelevant.

The web page fact sheet posted by EPA on its website on August 16, 2002 athttp://www.epa.gov/wtc/factsheets/fabrics.html states the following:

There are two key studies, which were conducted for EPA, which examined the

effectiveness of various cleaning m ethods on carpets impacted by asbestos. The firs t,

Evaluation of Two Cleaning Methods for Removal of Asbestos Fibers from Carpet (1),

found that cleaning asbestos- contaminated carpets with a hot-water extraction cleaner

was m ost effective, reducing asbestos levels by approximately 70%. The second study,

Evaluation of Three Cleaning Methods for Removing Asbestos from Carpet:

Determ ination of Airborne Asbestos Concentrations Associated with Each Method (2),

again found that a hot-water extraction cleaner was most effective, producing a 60%

reduction in asbestos levels in contam inated carpets. [Both studies used EPA’s

ultrasonication test method to establish the 70 and 60% levels.]

The first study spread asbestos on carpeting and used a steel roller to embed the

asbestos in the carpet; the second study used carpet from an asbestos-contaminated

office building in which the asbestos had been embedded in the carpet by normal foot

traffic. Note that if your carpeting was cleaned prior to reoccupancy, the dust and

whatever asbestos it may have carried had not been embedded in the carpet and the

cleaning may therefore have been m ore effective (m eaning a greater reduction in

asbestos levels).

However, because of the results of these studies, EPA cannot guarantee to residents that

all asbestos fibers, if present, can be removed from fabric items. EPA anticipates that

available cleaning methods for fabric items that were significantly impacted by dust or

debris may not be sufficient to address the concerns of residents or EPA's concern for

people's long-term health.

W ith this information in mind, EPA recommends that residents consider replacing some

or all carpets, upholstered furniture or draperies if their home was impacted by W TC dust

or debris.

...If a resident decides to discard fabric materials, EPA will remove and dispose of them as

part of the cleaning program, and will provide residents with contacts at the American Red

Cross (ARC) or other service agencies that may be able to provide reimbursem ent

assistance.

[Note that EPA is replacing all carpeting and upholstered furniture at government expense

in residents at the Libby, Montana Superfund site. This disparity in treatment of NYC

residences is egregious.]

- 3 -

Brookfield, CT township using ultrasonication extraction for both carpets andseat cushions in asbestos contaminated high school auditorium

The Brookfield CT school system is undergoing asbestos abatement over the summer monthsafter the confirmation of extensive asbestos contamination in several schools. The followingtable shows “before” and “after” data for asbestos in carpet, seat cushions, and curtains in theBrookfield high school auditorium.1 Attached to the end of this memorandum is a news articleshowing pictures and describing in detail the extensive cleaning efforts that were undertaken. Asseen from the following table, the cleaning was not effective in removing the asbestos.

ASBESTOS TESTING, BROOKFIELD HIGH SCHOOL AUDITORIUM

all results in units of asbestos structures per square centimeter (s/cm 2)

Seat Cushions - Before and after sampling points are not necessarily for the same seats.

Before abatement

ASTM microvacuum method.

After HEPA vacuuming, steam extraction

EPA ultrasonication test method

less than 267 12,835

535 6,417

1,070 23,179

3,210 42,159

1,605 35,861

535 58,989

less than 535 32,260

1,070 16,215

less than 3,243

35,110

Carpet - Before and after sampling points are not necessarily for the exact same areas of the carpet.

Before abatement

ASTM microvacuum method.

After HEPA vacuuming, steam extraction

EPA ultrasonication test method

less than 535 115,521

535 405,383

2,675 51,616

less than 891

less than 535

As can be seen, the ASTM microvacuum testing for the Brookfield auditorium before cleaningwas unable to detect the elevated levels of asbestos. Obviously, the carpet and seat cushionswould be more contaminated before cleaning than after. But the ASTM microvacuum resultswere LOWER than the ultrasonication results after cleaning.

- 4 -

Stuyvesant High School carpet and seat cushion testing

Stuyvesant High School was contaminated with asbestos from the fallout from the World TradeCenters. The auditorium carpet was cleaned with HEPA vacuuming and some type of wetextraction method. After cleaning the carpet was tested with the superior EPA sonicationmethod. It was found to contain from 60,000 to 2,500,000 structures asbestos per squarecentimeter, which is unacceptably high.

Stuyvesant appears to be avoiding additional testing using ultrasonication methods based in parton the advice of Mr. Howard Bader, the consultant hired by the Parent Teachers Association. Reportedly, Mr. Bader is claiming that EPA’s ultrasonication method is “new” and that it is onlya “research method” and that it is “impossible to relate the results of ultrasonication [as opposedto ASTM microvacuum results] to hazards.”

Mr. Bader is incorrect. The EPA method, even if newer, would take precedent over any ASTMmethod, since it is an official EPA method which underwent all the necessary impartialgovernment review prior to its promulgation. Furthermore, the EPA ultrasonication method waspublished in final form in 1993, two years earlier than the 1995 ASTM microvacuum method, soit is not in any way “new.” Furthermore, the EPA method is hardly a research method; it isoffered by over 12 major asbestos laboratories, in some cases at prices lower than the ASTMmicrovacuum method!

As far as the claim of not being able to relate the results to possible hazards, Mr. Bader is againwrong. As seen from the beginning of this memorandum, EPA has interpreted the results fromultrasonication studies of carpets to be a reliable indicator of the fact that neither HEPAvacuuming nor wet extraction processes will remove embedded asbestos, and that after the WTCcollapse citizens should consider disposing of carpet and other fabric items.

Mr. Bader has been incorrect in his understanding of ultrasonication extraction before. On May17, 2002, Mr. Bader sent me an email claiming that EMSL Laboratories could only perform 10ultrasonication extraction tests a day, and this was the reason that EMSL would not be able toperform ultrasonication tests of carpet for EPA during the free testing of residences inManhattan. I suspected that this information was incorrect, and contacted EMSL laboratoriesmyself. EMSL informed me that it would be using other laboratory locations for the EPA testingand therefore was not limited to only 10 ultrasonication tests per day.

Interestingly, Mr. Bader stated in his email that he did not have the necessary expertise tocomment on whether higher volume air sampling should be used to test residences in Manhattan. EPA will be performing this more sensitive air testing, because the AHERA air clearance testcannot detect the very low asbestos levels of concern because too small a volume of air ispumped. It is like trying to find a needle in a haystack by only testing one handful of hay. Obviously, Mr. Bader is not as familiar with testing as other aspects of evaluating cleanuprequirements after the WTC collapse.

A copy of this email interchange between Mr. Bader, EMSL laboratories, and myself is attached.

The “seat beating” air testing that was done at the Stuyvesant auditorium is highly suspicious.

- 5 -

1. Rhode, Vernon (August 27, 2002) Personal communication. S & B Environmental, LLC, 40Valley Field Road S., Sandy Hook, CT 06482. S & B Environmental was contracted by theBrookfield, CT town Selectmen to independently monitory the abatement progress in theBrookfield school system. Note that the 8/27/02 tables from S&B Environmental had atypographical error in the units, showing asbestos concentrations as “structures per square mm"instead of the correct units: “structures per square cm".

Behind closed doors, with no independent observers, the seat cushions in the Stuyvesantauditorium were reportedly “beaten” while the air was tested for asbestos. No asbestos in the airwas found.

It defies all credibility that no asbestos would be found in the air after beating the seat cushions! Perhaps the monitors were not held within 2 feet of the cushions while they were being beaten,the breathing zone of a person who would sit in the chair. Or, the beating could have taken placelong before any air testing, or only immediately prior to air testing. Probably, too few seats werebeaten, even if the beating took place during the entire testing period. The air testing might nothave been at the high sensitivity levels planned in EPA’s testing for Manhattan (much highersensitivity than 2 s/mm2). Or, the operator of the air testing device might not have turned on theair pump or closed the portal to the air collection device. We do not know.

The seat cushions should be tested using EPA’s ultrasonication method, as was done for theBrookfield School System. Sufficient numbers of seats should be tested to insure some degree ofstatistical significance. Curtains and other woven fabrics throughout the school should also betesting using sonication. To allay any doubts and protect the children, all these items should bereplaced.

The News-Times: Local More than a dusting

The News-Times

More than a dustingBrookfield asbestos removal is painstakingBy Heather Barr THE NEWS-TIMES2002-08-11

The News-Times/Wendy Carlson

Asbestos removal cleaners vacuum up and wipe down equipment in the computer room at Brookfield High School.

The News-Times/Wendy Carlson Clean air is filtered out of the chemistry rooms from a tube connected to a machine called a microtrap, which collects the air and sends it through its filters to remove asbestos particles.

As temperatures soared into the 90s on a recent weekday, workers wearing protective fabric suits and respirators vacuumed and then wiped down a set of blinds in a bathroom at Brookfield High School. The air was as hot and heavy as in a sauna because no air conditioning or fans are allowed. Each set of blinds takes up to an hour to clean.

Such attention to detail is required when removing asbestos fibers. That is why crews have been working 24-hours a day to clean all four schools in Brookfield so they can open by Aug. 27. Day workers are bused from New Jersey every day, and some supervisors and project managers have been living at the schools.

Supervisor and foreman Marvin Aguilar’s home for the last month has been the high school.He taped together two cots in a school office and used them as a platform for an inflatable mattress.

On one wall he taped pictures and letters from his family, which drives from New Jersey on weekends to visit him. On another wall is a poster showing the inside of the human body, a reminder that his temporary home will revert to a nurse’s office when school begins.

Aguilar said it is hard to be away from his family, but he added the job of cleaning asbestos from the schools is important to him.

"Imagine your child exposed to something like this,” he said.

ä

"There is no tool, no machine or no miracle,” said

http://www.newstimes.com/cgi-bin/dbs.cgi?db=news&view_records=1&id=33793&Print_Story=1&ssi=1 (1 of 5) [8/13/02 1:33:16 PM]

The News-Times: Local More than a dusting

The News-Times/Wendy Carlson George Stokes III, the senior project manager, stacks up some of the cleaned items that have been put in storage and surrounded by plastic.

Erin Kiernan Workers steam clean seats in the auditorium. Later, cloth samples are removed to insure asbestos does not exist.

George Stokes III, senior project manager of PT&L Contracting Corp.

"The only way to clean top to bottom is 100 percent pure labor.”

The tools of an asbestos cleaner are both specialized and mundane.

Each worker, who is certified to do asbestos clean-up, wears a full suit of Tyvek, material that keeps out dirt and dust while allowing body heat to escape. Some also wear gloves, Tyvek booties over their shoes, Tyvek hair covering and respirators that cover the mouth and nose.

After sealing a room, a worker goes through with a leaf blower, aiming jets of air at the floors and walls. The object is to make any asbestos airborne so it can be sucked into a "microtrap,” a three foot square box with three filters.

Clean air is vented outside the building.

After the leaf blower makes all dust airborne, workers go over every surface with a specialized vacuum cleaner that also has three filters.

Stokes said a Hepa vacuum will trap 99.97 percent of the asbestos it picks up.

Finally, after the vacuuming, every surface or object is wiped up to four times with four different cloths.

Room radiators are cleaned using the same process, but the radiators, where much of the asbestos seemed to gather, are sealed off from the room with a plastic bubble around them.

The air in the bubble is then sampled before the plastic is taken down.

Most of the workers are originally from South or Central America. Marvin Aguilar, a general foreman, walks around the high school with a radio instructing workers in Spanish. Supervisors who do not speak Spanish use red lasers to point out to workers which sites need to be cleaned.

http://www.newstimes.com/cgi-bin/dbs.cgi?db=news&view_records=1&id=33793&Print_Story=1&ssi=1 (2 of 5) [8/13/02 1:33:16 PM]

The News-Times: Local More than a dusting

Erin Kiernan The cleaned sections are covered in plastic until removal is complete.

Visitors occasionally arrive for tours. U.S. Rep. Nancy Johnson, R-6th Dist., walked through the building during the last week of July.

Before a room is cleaned, workers remove all the objects inside, from desks to crayons. They are cleaned in holding areas that are sealed from the rest of the building.

In the high school’s ceramics room, students still had items in the kiln when school was closed early for the year. Each object had to be removed carefully and cleaned.

"When we cleaned we paid attention to students’ projects to make sure they were not damaged or destroyed. We know a lot of students spent time on a project. We are sympathetic to their needs,” said Stokes.

"Besides radiators, laboratories (chemistry or biology rooms) were difficult to clean because of chemicals and items in drawers,” said worker Marco Salgado. "You had to move things one by one.”

Every item in a contaminated area must be cleaned, including light fixtures, the insides of exit signs, lockers, and the like.

Cleaning a computer takes up to 90 minutes. All computer mouses and keyboards were thrown out, along with about 25 computers deemed to be so old they were not worth cleaning.

A total of about 190 computers were cleaned and wrapped in plastic to await an air sampling of the room in which they were sanitized.

The dust collected in the vacuums, filters and rags is bagged, labeled as dangerous, and taken to a landfill that accepts asbestos.

A trailer outside the school has a shower and an area for the workers to clean up before going home if they wish.

ä

High levels of asbestos were found in Huckleberry Hill School in May after music teacher Margaret Fitzgerald, acting on her own concerns, hired a company to test her room. Further testing by the district found that all four schools were contaminated.

Students were transported to other schools in the region to for several days at the end of the year. The town authorized $900,000 toward a clean-up, and state officials approved use of a

http://www.newstimes.com/cgi-bin/dbs.cgi?db=news&view_records=1&id=33793&Print_Story=1&ssi=1 (3 of 5) [8/13/02 1:33:16 PM]

The News-Times: Local More than a dusting

disaster relief statute that allowed the town to issue short-term bonds for another $3.2 million. An Aug. 27 referendum is scheduled for residents to vote on whether to pay to cover the notes.

Infinity Environmental Services of New York was hired to clean Huckleberry Hill and Whisconier Middle schools and PT&L Contracting Corp. of New Jersey was contracted to clean Center School and the high school. Work began in early July.

ä

A large piece of asbestos hangs from a return air intake duct at Brookfield High, looking like five or six gray cotton-balls stuck together. Stokes took a photo of it before a small robot on a tether went through the duct sweeping up all dust. The larger ducts were cleaned by workers who crawled through them.

Not every inch of each school had to be cleaned so vigorously.

About 11 rooms in Huckleberry Hill School, 45 rooms in Whisconier Middle School, 12 rooms in Center School and 70 rooms in Brookfield High School were completely cleaned.

Cleaning started after all rooms and areas were tested for asbestos. A color-coded map was prepared of the inside of each school to guide workers.

To separate non-contaminated rooms from contaminated areas, large blankets of plastic were attached to doorways throughout the building. Signs warning "Asbestos: Cancer and Lung Disease Hazard,” were posted throughout each school.

In some rooms, the specialists cleaned only the radiators and air ducts, and janitors cleaned the rest.

Some carpets were removed, but the rest were steam-cleaned. Contractors were able to save hundreds of cushioned chairs by steam-cleaning them.

Asbestos levels are ruled safe only after each school gets a final test of air that is circulated with blowers.

And then Aguilar, the supervisor and father of four, will be able to pack up his photos and letters and finally sleep in his own bed again.

"I miss my family,” he said.

Contact Heather Barr

at hbarr@newstimes.com

or at (203) 731-3331.

http://www.newstimes.com/cgi-bin/dbs.cgi?db=news&view_records=1&id=33793&Print_Story=1&ssi=1 (4 of 5) [8/13/02 1:33:16 PM]

Cate Jenkins

05/20/02 01:47 PM

To: amy.rutkin@mail.house.gov, envjoel@ix.netcom.com, ihconsult@msn.com, jan1006@comcast.net, actsnyc@cs.com, paulwoodsbartlett@hotmail.com, artandpolitics@yahoo.com, mclarke@shiva.hunter.cuny.edu, flynnktm@aol.com, lisette.morton@mail.house.gov, dave@nycosh.org, jbennett@nycosh.org

cc:Subject: Howard Bader's misrepresentation of EMSL's capacity

to do carpet sonication tests under EPA cleanup contract, and concurrence with my comments on other issues

As per the below interchange between Howard Bader, he director of EMSL Laboratories, and myself, it is apparent that EMSL Laboratories does have the capacity to perform sonication extraction testsof carpet samples for residents under the EPA downtown cleanup contract.

Howard Bader's email to me claiming that EMSL did not have the resources to do this was erroneous.

The following from Robert DeMalo from EMSL Laboratories makes it clear that EMSL can perform these inexpensive tests, even though they are labor intensive. Each sonication extraction of carpets would only cost $200 on the open market, substantially less if under a large contract with the additional cost savings.

Sonication extractions of carpet are important. They will showover 100 times the amount of asbestos that a microvacuumsample will show.

Carpets are resevoirs of asbestos, andcannot be cleaned effectively even with HEPA wet extractionprocedures. Typical professional asbestos abatement procedures simply dispose of asbestos contaminated carpet.That is what they are doing in Libby, Montana.

Howard Bader does concur with me on the other aspects of my comments on EPA's draft scope of work and testing, however.

_______________________________________________________________________________________________________________________________________

"DeMalo, Robert" <RDemalo@EMSL.com>

05/20/02 11:04 AM

To: Cate Jenkins /DC/USEPA/US@EPA

RE: Howard Bader's quotation of Robert DeMalo

- - - - - - - - - - - - - - - - - - - - - - -

Dear Ms. Jenkins,

EMSL is currently under contract for both the outdoor and residential sampling events with the USEPA. Presently, we utilize our Manhattan branchfor the ground zero samples and our Long Island branch for the landfill samples. The phase 2 of the residential work has not

been clearly defined.I was told testing will be made available to approximately 15,000 residencesthrough a hotline. Furthermore, an upper limit of 75,000 samples was estimated. The ability for EMSL to handle this amount of samples will depend on at what rate the samples are submitted to the laboratory and whatturnaround time is expected. I do not have this information at this time.

I can tell you that EMSL plans on utilizing, at a minimum, our 6 regional labs that are the closest proximity to NYC: Manhattan, Long Island, Elmsford, Piscataway, Buffalo and Westmont, NJ (Corporate office & Lab). Ifthe sample influx exceeds these 6 labs, then I will consider utilizing our other 15 nationwide labs. The carpet sonication method is labor intensive,especially on the preparation steps.

I did quote Howard Bader 10 samplesper day, however this was only for our Manhattan lab. Until I can get aproject schedule, I cannot predict what laboratory capacity will be. I hopethis information is helpful.

Thank you,Robert De Malo

_______________________________________________________________________________________________________________________________________

-----Original Message-----From: Jenkins.Cate@epamail.epa.gov [mailto:Jenkins.Cate@epamail.epa.gov]

Sent: Monday, May 20, 2002 10:11 AM

To: rdemalo@emsl.com

Subject: Howard Bader's quotation of Robert DeMalo

- - - - - - - - - - - - - - - - - - - - - - -

Rob,

I just left you a voice mail message. The attached is an email from Howard Bader, who contacted you regarding the EPA contract. I was wondering if he was quoting you accurately.

As I stated in my voice mail message, I have no official duties related to the EPA contract. However, in l discussions with concerned citizens, I was suggesting offering them the option of having sonication extraction testsperformed on their carpet. I had not previously contacted your laboratory regarding sonication extractions under the EPA contract, or intend to in the future. I had called you earlierasking whether your lab could perform these services on behalf of private parties who

were wondering about their options for testing a co-op in Manhattan, not related tothe EPA contract.

Since Howard Bader is quoting you now,I would personally be surprised if EMSL were planning on fulfilling all of its analytical capabilities with only one laboratory out of the many available EMSL facitilies, or that if requested by EPA to perform additional services that did in fact tax current EMSL resources, that EMSL would not consider increasing the available staff either trained to do sonicationextrations or consider sub-contracting out sonication extractions to other laboratories.

Thank you very much for clearing up any confusion.

Cate Jenkins703/308-0453

_______________________________________________________________________________________________________________________________________

Howard Bader <hbader1@nyc.rr.

To: Cate Jenkins /DC/USEPA/US@EPA cc: "Rutkin, Amy" <Amy.Rutkin@mail.house.gov> Subject: Re: Response to your tele message 05/17/02 02:22 PM

- - - - - - - - - - - - - - - - - - - - - - -

Cate, my voice mail message to you was not intended to say I disagreed withyou, rather it was to express concerns I had. I spoke to Rob Di Malo of EMSLbefore my call to you and he thought they would be heavily burdened withjust doing the air and microvac samples. He thought EMSL could only do 10sonication samples per day. I'm not sure how many other labs do this work.This may be a huge problem for a potential 15,000 apartment project. I'm also concerned that we can establish an agreed upon criteria for evaluating the sample results.

I agree with you that the publics health should come before cost or convenience, however we need to make sure whatever werecommend can actually be accomplished (given the time parameters athand).

Since that time I have read your detailed e-mail. I agree with you onall the remaining items except the air sample analysis methodology, I don't

have the expertise to comment this.

_______________________________________________________________________________________________________________________________________

----- Original Message -----

From: <Jenkins.Cate@epamail.epa.gov>

To: <hbader1@nyc.rr.com>

Sent: Friday, May 17, 2002 12:38 PM

Subject: Response to your tele message

- - - - - - - - - - - - - - - - - - - - - - -

Howard, I could not get you by phone.But if you are reading this, you got myemail of the comments I sent Amy.

The sonication extraction only cost $250.It is hardly a research option. Many labsoffer it. And remember, we are talking aboutprotecting citizens. We do not need toconsider bogging down the labs. Not manypeople will choose to use it. You can'tsay it will stretch the resources of anylabs, because the volume of the othersamples they will be doing far exceedsany sonication samples.

I talked to the president of EMSLwho got the indoor monitoring subcontract,and they can do it. Also, you seemeddubious about the high volume air samples.But EMSL already says that EPA is goingto require 4800 liters of air, so I am not askingfor anything not planned.

My attitude is that we really need to beprotective of the citizens here. It may bethat industrial hygienists did not offer theseoptions to New Yorkers in the past, but thatshould not influence their advice now. I reallydo not think that any IH is at risk for liabilityby NOW recommending these more protectivetests because they did not do them in the past.

Now that the government is paying the bill,the lower quality testing recommended byIH's in the past should be forgotten and excused because the citizenwas paying for it.

Cate

'/PB93194355 i 1111111111111111111111111111111

''''----I j

----~

Methods for the Analysis of

James R. iVlillelte, Ph.O./\ P. J. Clark, B Kim A. Brm:kelt, Ph.D., C and R. K. Whecles"

(Key words: Asbestos, Transmission Electron Microscopy [rEM), Carpeting, Ultrasonic Treatment, Microvacuum) ! NTIS is lButho;ized to reproduce and sell this i report. Permission lor lurther reproduction ~~e Dbtai~ Irom the ~opvrighl owner.

Assessing asbestos fiber contamination in a carpet is compncated' by the nature of the carpeting - be<ause of the pne's rough surface and thickness, samples cannot be collected directly from carpet for analysis by TEM. Two indired methods are currently used by laboratories when preparing samples for measuring the amount of asbestos present in carpet material. One is an ultrasonic shaking technique which requires that a portion of the carpet be cut out and sent to the laboratory. The other is a micro­vacuuming technique which has been used generally in the assessment of asbestos in settled dust in bundings. It is not destructive to the carpet. Both methods utilize TEM to identify, measure and count the asbestos fibers found. Each can provide important but different information when an assessment of the level of contamination of carpeting is being made. The ultrasonic shaking .. (bulk-carpet sonication) technique gives an index of the asbestos contamination throughout the entire carpet piece and the micro-vacuuming technique gives an index of the readily releasable asbestos fiber from the carpet surface.

A major concem in builJings Iha! contain asbestos-con­

taining material (ACM) is the extent to which the carpet may serve as a reservoirofasbes!os fibers that have been

released from the ACM by one mechanism or another. I The Asbestos Hazard Emergency Response Act (AHERA) requires that all carpel in areas of school buildings in which ACM is present be cleaned with either a high-efticiency particulate air

Environmental Choices Technical Supplement· March/Apn11993

(I~ EPA) lilterecl vacuum cleaner or a hot water extraction cleaner (~teal11 cleaner). The potential for airborne asbestos fiber n':l:nlrainml:nt during ca~t cleaning activities was shown in stuJil:s in which airbome asbestos concentrations were found to be bctwl:en two and fourtimes greater during cleaning than before the carpet cleaning activities.~·:-

There arc currently two Illl:thods used by the authors' labora­tories forcollccting and indirectly preparing samples toevaluale the amount of asbestos in or on a carpet. Direct collection and direct preparation procedures such as tape lift sampling have been investigated and cannot be used effectively with carpeting. There arc currently no standard EPA methods for assessing asbestos in carpeting. One of the methods which is used is an ultrasonic extraction procedure in which a square piece cut from a carpet is milJly ~onicated in water with surfactant to relea!ie Jsocstos fibers both on the surface and embedded in the carpel. This method is similar to one that ha~ been published about how to measure asbestos lihers in clothin!! and fabric materials." nle other method is a vacuuming proced~re which uses a moelilied air sampling cassette to vacuum a sample of dust primarily from the surt-ace of the carpet. The microvacuuming technique is non-destructive to the carpel. Both methods use the particle dispersion techniques devel­oped over the year~ for the analysis ofasocstos in drinking water.5.6

. The Ultrasonic Preparation Procedure

Samples of carpet arc collected by cuLting a piece t usually 10 centimeters by 10 centimeters) from the carpet with a rJzor blade or utility knife and placing it in a wiele-mouth polyethylene jar or zip-Ioc bag. In the laboratory. five (5) centimeter by five (5) centimeter squares of carpet are cut and placed carpet-side down in

a .h0Q9_f!!illiU!e! beak~E_~~t<liningJ9QITI!lli!lt~!S_~f.0.19'o solution . REPRODUCED BY

U.S. DEPARTMENT OF COMMERCE NATIONAL TECHNICAL INFORMATION SERVICE 21

of the surfactant aerosol OT or a 0.002% solution of the surfactant methyl cellulose in particle-free water. The beaker is placed in an ultrasonic bath for 30 minutes. The carpet piece is removed anu ri nsed into the beaker wi th 100 mill il itt::rs of particle-free water. The entire suspt::nsion (200 milliliters.) is then shaken vigorously by hand to disperse the particles and then alloweu to sit for twO minutes to allow the denser panicles to sink and the light particles to tloat to t he top. Atth i~ time. three measured al iqllots ofdi rferent volumes L .....• 11.. _. __ 11 \ .. _._,1/,\ __ .1 ,":,1." .... f:::'{",\, __ ~1I:1: ... __ .• ' ..... __ ........ _ ........ '"'~I \lI."'tUc.lIIY '-'II\,; ~ lJ. \\:11'\ I\J) dilU IIllJ \.JVJ 1111111111. .... ..&.')) UI\,., ",,,llU"-'l\,..U

with disposable graduated pipettes 1/4 to 1/2 inch below the water surface in the beaker. The aliljllllt is mixed with particle-free water to make 50 mi IIi I iters and Ii ltered through a 0.22 ~lIn pore size mi .\cd cellulose ester lilter or a 0.2 flill polycarbonate lilter backed by an 0.45 fli11 rore size cellulose ester lilter. If by visual observation. the initial beaker cont~lins large non-asbestos fibers (carret material). the entire suspclI-;ion is passeu through a coarse stainless steelll1t::sh screen. The filters are dried and prepared for TEivI analYSIS according to the NIOSH 7402 preparation rrocedure (cellulo~e ester lilter)7 orthe Yamatc. et al.. rrocedure (rolycarbonate tilter).~ Atleast two TEivI grids from d i ITerent areas orthe Ii Iter arc prepared for each sample. After the three liltrations arc completed. the remaining suspension is transrerred to a graduated cylinder and the volume recorded. 1l1is volume is auded to the volumes of the measured aliljuots to obtain the total volume of the sample. 1l1is accounts for the variable amount of water absorbed in the carpet during proces.-;ing. A sample blank is prepared in ~in identical way as the sample. although no carpet segment is actually used in the ultrasonic rrocedure.

The Microvoc Technique

Samples which arc collected by microvacuuming are commonly referred to as microvac samples or .microvac dust samples. They are collected byvacuuminga lOOcm2 area(orotilcr known area) of carpet wi th a membrane fi Iter air-sampl ing cassette and vacuum pump. 1l1e samrling assembly consists of a 25-mm diameter mixed cellulose ester filter contained in a three-piece standard J\ HERA'J air casseHe with a one (I) inch piece of tubing

. ~Iltached to the face cap as a noale 1 0. 1l1e end of the n07.z1e is cut at 45 dq~rees. 1l1e cassette is connected to a personal sampling rump with tlexible tubing. The pumr and cassette assembly are calibrated to 2 L/min. The I 00-cm2 area is vacuumed by moving the tilter cassette nozzle across the carpet to agitate the carpet pile .. 1l1e carpet is vacuumed· for approximately 30 seconds in one direction. then another 30 seconds in a direction 90 degrees to the first. Arterone minute of vacuuming. the pump is tumedoff and the fi lLer cassetle nozzle is plugged and the cassette is labeled.

In the laboratory. the unopened microvacuuming cassettes are wet-wiped and then rrcrared for analysis under clean room condi­tions. 1l1e cassettes and filters are rinsed out with particle-free water and refiltered through a second lilter which is used in the analysis. 1l1e original filter is washed during the sample prepara­tion procedure but otherwise is not used in the preparation.

Specifically. the plug from the nozzle of the cassette is removed and the cassette is filled with approximately 10 ml of pretilLered water. The plug is replaced and the cassette is shaken vigorously by hand fortwo to three seconds. The entire cap of the cassette is removed and the suspension poured into a pre-cleaned

.,.,

200 ml glass medical specimen bottle. All visible traces of the sample are rinsed into the specimen bottle with a plastic sljuin bottle of filtered water. This procedure is repeated two additional times for a total of three washings. Next. the nozzle is rinsed two or three times into the specimen bottle. Typically. the total amount of water used in the rinse is arproximately 70 to 75 mi. The water level in the specimen bottle is then carefully adjusted to 100 ml with preti Itered water. The rH of the water is adjusted to 3-4 using a 1.0%

for three minutes to make a uniform suspension. Aner two minutes of settling. a measured volume of suspension is extractl:d with a graduated pirette inserted halfway into the sample solution. The aliquot is mixed with particle-free water in the tiller funnel and tiltered through a 0.22 flm pore 'iize mixed cellul()~e e~tcr tiltt::r backed by an5.0 flm rme size cellulose ester Ii Iter. The Ii Iter is dried and prepared according to the AHERA air samrle rrepar~ltilln

procedure. A samrle blank is prepared in an identical way ~IS the sample. although no carpet segment is actually vacuul1ll:Li.

Asbestos Counting

In the transmission electron microscope. the number of each type of asbestos structures. chrysotile or amrhibole. is detennineu by examining a known arcaon the grid in terms of a number of grid openll1gs. The asbestos fibers are identitied on the ba.,is of morphology. selected area electron diffraction (Sf\ ED I and/or energy dispersive X-ray spectrometry (EDS).

The samrles arc counted following the EPA (Yamatc) Provi­sional Method 'or the AHERA cOllnting rules. Thc choice of counting methods depends on the par1icular interest of the anal: sl. 1l1e Yamate counting rules provide more information about the sizes of structures found by the analyst than do the AHERA counting rules. The amount of asbestos in a given sarnrle is expressed as structures per square foot. structures per sljuarc centimeter or structures rcr square meter. 1l1C value is calcubted using the following equation:

EFAx 100 X NOSTR = STRUCTURES /AREA OF

GO X GOA X SPL X V THE CARPET

NOSTR = Number of asbestos structures counted in the, analysis

EFA ::: Effective filter area of the final sampling filter in square millimeters

GO = Number of grid openings analyzed

GOA = Average area of one TEM grid opening in square millimeters

S PL = Amount of carpet area sampled (in square feet or square centimeters)

v = Volume of sample filtered

Environmental ChoicesTedtnical Supplement. March/Apn11993

- • ----------------'J

Table I-Results of Carpet Analyses for Asbestos Samples Randomly Chosen in Cafeteria Carpet After Conventional (Dry) Vacuuming (all values in asbestos structures per square centimeter)

Sample # LAB A (Sonication)

5,400,000

2 3,050,000

" 3 *68,000

4 3,600,000

5 3,400,000

6 4,300,000

7 3,200,000

8 2,000,000

*at detection limit

Data on Precision and Percent Recovery

Studies on tile precision and level of recovery of asbestos of tile hulk-carpet piece ultrasonic shaking (sonication) technique ;Uld the Illicro-v,lcuumingh:chniquc were perfonned as part of the 198X EPA study.'! Six samples were collected using each method from carpet artilicially contaminated with approximately I billion (I x I ()'l) asbestos structures per ~quare foot (sift) or I.OX x IOOstr/cm2. nle artilicial contamination was accomplished by spraying a

'known areaof a carpet with a water solution of known asbestos concentration. Because there was no independent way to measure the concentration of asocstos on the carpet. no.accuracy detenni­nation could be made. However. the relative cl"liciem:y of recovery of onl.! method to the other could oc assessed. nle mean asbcsto~ recovery using the microvacuuming technique was 2.3.'( 107 s/IY! (2.5 x 10-1 s/cm2). This was approximately 3% of the mean recovery of till.! hulk-carpet sonication extraction technique which was 7.9 x lOx sjrt2 (X.5 x lOs s/cm2). nle calculated coefficient of variation (CV) for the microvacuum technique was 166%. The CV for the bulk-carpet sonication procedure was 43%. It should be noted that thl.! values given in referl.!ncc 2 for structures per square foot are the correct values. I I Thl.!rc was an English/metric conversion error in thl.! article which provided incorrect values for structures per square meter throughout the paper.

A similar set of tests using "real world" carpeting that had been contaminated over a· 15 -year period of nonnal use has been pcrlomled by the authors' laboratories. Thc carpet samples were collected from a cafeteria in the Social Security Administration in Baltimore. Maryland nlccafcteria had an acoustical plasterceiling

LAB B (Sonication) LAB B (Microvac)

4,800,000 21,000

3,300,000 30,000

*5,400 *<350

3,800,000 74,000

3,000,000 50,000

2,500,000 95,000

3,600,000 18,000

4,700,000 35,000

containing I to 5% chrysotile. Ali furnishings had been removed from the cafcteria and the area had been vacuumed with a conventional dry vacuum ckaner twice before the samples were coliectell Previous use and traffic patterns were not taken into account in collecting the samples. The samples were collected in a random manner and some samples may have been from areas where an appliance such as a soft drink machine may have stood previously. The data which include some interlaboratory compari­sons arc presented in Table I. Although there appears to be one outlier in the data set. thl.! relative stands deviation was calculated using all eight data points for each mcthod. The Sr for the microvacuum technique was 77'10 and for the bulk-carpet sonica­tion procedure was 51 Ck for Lab A and 47% for Lab B. nle mean recovery of the microvacuuming technique compared to the bulk­carpet sonication prC?Cedure was 1%.

Discussion

The answer to the question about which method is best for assessing the asbestos level in carpeting depends on the specitic question being asked. In the 1988 EPA carpet study the authors

concluded that sonication of bulk -carpet samples provided a more precise and accurate estimate of asbestos concentrations in carpet than the micro-vacuuming sampling technique. Their conclusion was based in part on data which showed that the microvacuuming technique was shown to recover signi ficantly less asbestos from the carpet than the ultrJsonic extraction technique.

The fact that one technique is more efficient in recovering fibers than the other may be important for some studies investigat-

ing the cleaning oflhe totaf carpet. However. there is reason to believe Ihat carpets can act as a trap for asbestos fibers and that activities shOI1 of carpet removal may not disturb asbestos fibers which have worked their way deep into the carpet pile.

For Ih()~e fibers which can be readily rcentraincd into the air ·Crom the carpet surface during cleaning activities the lllicrovacllull1ing procedure may be more appropriate. This is reasonabk considering that the 111 iCfovacUUl1l ing procedurecollecls

Ilhl'r~ t"mm the top layer of thl:! carpet and the bulk-carpet sonication proc"dun: shakes out more tibers which may be embeuded (Jccpin the carpet pik. The tlala show that the sonication of blllk-c~lrpct samples is a more precise procedure than the microvacuumillg procedure. However. the microvacullll1ing procedure has an ;tdv;l1ltage of being non-destructive. While some builcling owners

may be willing [0 ha\'\': a rieu:: of carpL:ting cut from their building

if tile carpel i~ 10 he removeu, it is k~!'o lil-.dy Ihat a piece Illay h..: ":Ul

if Ihe int":llt is to study th..: c!"fectiv..:ness of various cleaning

procedures. It is probable tilat a relationship exists h.;t\\ieen carpet con­

tamination and air levels of asb..:s!os produced during cleaning ami olh..:racti\'ilie~. For a given carpet. ,I higher level of'asbestos in the carpet would be expected 10 produce a high..:r level in the air for a particular activity. The two methods described here will provide the basi~ f(1r eV;lluating the !evcl of asbestos contamination in carpeting to be compared wilh levels of asheslos in the air produced during studiL:s or r..:-cntrainment.

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REFEREt\CES

II Wilmoth. R. e., T.J. Powers ;111r1J. R. f'vlillettc, "Ohscrvatiofl!>011 Stmlks Useful to Asbc~tos 0&;0.1 Activities". Microscope. 39:299-:\ 11 ( ISl(1).

1) Komin,ky. J.R" R.W. Frcyberg. 1. Chcsson. W.e. Cain. TJ. Pov,.!.:rs, T.J. ami R.e. Wilmoth. "Evalualion or' Two ClI;llning Mcthntls I'or the Removal of Asbe,lOs Fibers I'rom ClrpCt." :\m.11Id. /'h" Assoc . ./. 51 (9):5(JO-504. (1,)<)\).

J) Kamlll"k),. 1.R .. Frcybeq;. R.W .. K.A. Bmd;ell. B.A. HolicH. Re. Wi Il110th. and PJ. CI'lrJ.;, "Evaluation otThrec ClI;;lI1ing Methods for Removal or Asbe~!Os Fibers from Carpet and Associnted Airhorm: Fiber Con..:entralions." Presented at Environmental Management ·91.ll1e Ninlh t\nnual Convention and Expt)~ition or tile EnviromlH:l1wl Inlonllarion Assodallon. April X. 19l)2, Pillsburgh. Pa.

-I) Chalticld. E.L" Analytical Prmocol I'or Deh.:rmillalion of c\,bcs-10 ... COf1Wl11lnaliolJ of Chlliling and Olher F;lbric~ ". ,Vlic/'IJ.\('O/i<'. 3)0):11 1-222 (I'J90).

5) Chalficld.EJ. ami \1.J. Dillon. ,'\lIulrticallllclllOdJ()rlii'lcJ'llIi/1I/' lioll ofashcslOsj7hers ill H·ma. U.S. EPA-nOO/-l-X4·0 .. B. 1 Sl)O)].

6) Br:lt.:kell.K.r\.. P.J. Clark ,mu 1.R. Millcl!c. "A iVh:lhml for Ill.: Analysi, of Asbl.!slOs Finers in Water Using MCE Filters". Micros('()/ll'. -IO( 3): 159-163. ( I 'N::: 1

7) Carter. J.W .. P./\. Baron and D.G. Taylor. "~!OSH 74n:::." NfOSH MWllwl of ,\lIu/l'li( al MCliIOr/.,. Pp. 740 I-I - 7401-7 ( 19S7).

~) Yam;!te.;\1.. S.c. A~arwa!. alll! R.D. Gibbons. ";\Ic!houlliogy for IIlI! Me;lsun:mcnt of Airhome Aso.:slOS Conc!.!ntralions hy Eb:lrnn Micro:.copy". Dm!1 Hel'OI'!. Wa.\hingzon. D.C.: Ortiec of Research inti Development. U.S. EPA. COnlr:lct l\o. /1)0)-02-3260, IlJX-I.

lJ) U .S . .EPA. Ashestos Ha:r.;Jrd Emcrgcl1I.:Y Response ,'\'ct (AHERA I Regulations. (-10 CFR 763 Subpan E). Oct. 30. I <)X7.

IU) Microv:l!;ulIming sampl!.!rs arc (;omlncrcially available from Environll1<:lrics. Inc .. 1019 Banklon Dr .. Charl!.!ston. S.c. :::9-l06

II) Personal communication: KUl1)illsky.l.R.'alld R.W. Freynerg.

EnvironmelllalQuality Manag!.!I11CrH. Inc .. CilKinnali, Ohio.

A lTI [OR Af-1'lUATIO:liS

A .Iallles R. Mil/me. PhD .. ami R.K. Whl'l'IL'.I'. i),IVA. /I/C, 550()

Oak/}I'(wk Pkwy .. tl2()(). Norcross. GA 30093.

BpI Clark.. U.S. £lIl'imlllllcnW/ Pm(('uioll Agency Risk i?edllclioll Engineering uliJlIl'(lrory. Mai/slOp4.J5.::6 West ;Harrill LlItlter King Dr .. Cincinnati. Off 45268.

C Kim A. Bl'ackell, Pit. D .. IT Corporarioll.11499 CheSler Road. Cincillilati. 01-145146.

Environmental Choices T edtnical Supplement. March/April 1993

TECHNICAL REPORT DATA (Pfet11t! read /nstTUclion!S 01'1 the ff!Veru IHf(Nl! COmplf!li~-;' -

1. REPORT NO.

EPA/600/J-93/167 3.; '. PB93-19.4355

4. TITL.E ANO SUBTITLE 5. REPORT DATE

METHODS FOR THE ANALYSIS OF CARPET SAMPLES .FOR.ASBES:rO~:-::-::-::-::-:-:-~~~~-::--___ ~ , . 6. PERFORMING ORGANIZATION CODe

7. AUTHOR(SI 1 2 8. PERFORMING ORGANIZATION REPORT NO.

Jim R. Millette Kim A. Brackett Patrick J Clark3 R.K. Wheeles1

9. PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM ELEMENT NO.

1. MVA, Inc. 5500 Oakbrook Pkwy, #200 Norcross, GA 30093 2. IT Corp. 11499 Chester Rd., Cincinnati, OH 45246 l1.CONTRACT/GRANTNO.

3. U.S. EPA 26 W. Martin Luther King Dr., Cincinnati, OH 45268

12. SPONSORING AGENCY NAME AND ADDRESS

Risk Reduction Engineering Laboratory--Cincinnati, OH Office of Research and Development-

13. TYPE DF REPORT AND PERIOD COVEREO

Final .lournal Artirlp i 14. SPONSORING AGENCY CODE

U.S. Environmental Protection Agency Cincinnati, OH 45268 EPA/600/14

15~SUPPLEMENTARYNOTeS Project Officer;:: Patrick Clark t513 569-7561; "Environmental Choices - Technical Supplement", Volume 1(2):21-24. March/April 1993

'''. ABSTRACT . ..p\

'" ~. Because of the nature of carpet pile, no s'amples can be directly prepared from carpet for analysis by transmission electron microscopy (TEM). Two indirect methods are currently used by laboratories when preparing samples for measuring the amount of asbestos present in carpet material. One is an ultrasonic shaking technique which requires that a portion of the carpet be cut and sent to the laboratory. The other is a micro-vacuuming~technique which has been used generally in the assessment of asbestos in se~tled dust in buildings. It is not destructive to the carpet. Both methods utilize TEM to identify, measure and count the asbestos fibers found. Each can provide important but different information when an assessment of the level of contamination of carpeting is being made., ___ =~_

17. KEY WORDS AND DOCUMENT ANALYSIS

a. DESCRIPTORS

Asbestos Transmission Electron Microscopy Carpet Indirect Preparation

18. DISTRIBUTION STATEMENT

RELEASE TO PUBLIC

EPA Form 2220-1 (R.v. 4-77) PREVIOUS EDITION 15 OeSOI..ETE

b.IDENTIFIERS/OPEN ENDED TERMS c. COSATI Field/Group

Asbestos ~ GS-.·Minera 1 s)

RT- Sertentine) lectron Microscopy GS-Mi croscopy) RT-Microanalysis)

Particulate Sampling 'r.:'_';lmnlinr'l' RT_rnnron+r;:l . .;" ... ~

. 19. SECUf'(ITY Ct:ASS IT/lIS R~po,t) 121. NO. OF PAGES

UNCLASSIFIED 6 20. SECURITY. CLASS (TIiis-p<JR'" 22. PRICE

UNCLASSIFIED