Document jm0g6bZXE0Zkdx01GnLqEp5bk

W . R . GRACE U CO. construction PRODUCTS DIVISION vV '.'IrVjr-;i 000433 t75v6fl-SS STATEMENT DELIVERY BEFORE: Ta-Tit'V T1T.31Ur'1I1'n'TL,i,i*r"`n'J" ~ ^ a' UP mT*H* w^ V " 7 'D v- r, v ur* ttarpu*tiTivt w^ .* NATIONAL EMISSION STANDARDS FOR IARDOUS TO 3Z HELD: COMMENCING THE 15?H DAY OF FEBRUARY 1972 IN LOS ANGELES, CALIFORNIA A lo-Ojjl '.Ufl.l 0 (L. 9,!jM 'C U.o-v J A cv/-y PURPOSE Oo> uv*.', 7 ^ 0(e P? A,/. U, A- ; / : The purpose of W. R. Grace & Co., Construction Products Division ("Grace") in submitting this statement at this hearing of the Environmental Protection Agency ("ERA") is to request the ERA to clarify its proposed National Emissions Standards for Hazardous Air Pollutants relating to asbestos published in the December 7, 1971 issue of the Federal Register so as to clearly establish tha* th nrav na tion of piaster fireproofing containing less than 12% asbestos by weight is not a prohibited activity. It is Grace's belief that proposed standard Section 61.22(e) prohibiting "the spraying of any product which contains asbestos on any portion cf a building or structure" or "in an area directly open to the atmosphere" is in reaction to growing concern relating to asbestos emissions from spray-applied asbestos fireproofing. Grace shares this concern, a concern which it has long had. Grace believes, however, that the proposed standard prohibiting the "spraying of any product which contains asbestos" is much broader than necessary to protect the public from the hazards said to be posed bv asbestos nSoG, emissions and is basej__or> the assumption that "spray-applied asbestos fireproofing" and "the spraying of any product which contains asbestos" mean the sane thing. It is therefor important to clearly differentiate between plaster fire proofing containing asbestos and spray-applied asbestos fireproofing. SPRAY-APPLIED ASBESTOS FIREPROOFING Spray-applied asbestos fireproofing at which in Grace's Judgment the proposed standard is aimed is commonly 33? asbestos by weight. The asbestos is generally combined with mineral wool fibers and inorganic binders. The fibrous mix is then dumped dry into a hopper which fluffs the dry ' material. This dry material is then blown in a dry state to the point of application where it emerges from a nozzle which may be 2-3" in diameter. At the nozzle a water spray is introduced and- the dry fibrous material is blown through the spray causing the mix to be wetted and propelled to the surface to be coated. Because of this spray method, the fact that the wetted fibers are lightweight and the spray pattern quite broad, the opportunity for emission of asbestos fiber into the atmosphere in the application of spray-applied asbestos fireproofing is high. 2 7S"OG? D In addition, not only can overspray and rebound of spray-applied asbestos fireproofing become airborne in application, but overspray quickly dries out and it too can become airborne. (Attached hereto are photographs showing the application of spray-applied asbestos fireproofing.) (Exhibit A) plastep fi?.e?p.oofi::g For about 10 years Grace has been promoting a method cf fireproofing buildings with a process in which the fireproof materials are premixed in a slurry fora prior to application This Piaster firenrocfing basically is composed of vermiculite, gypsum, and less than 12? asbestos by weigh't in each 50-lb. bag. Each bag is then placed into a hopper with about 50 quarts of water. The mix is blended into a vet plaster slurry and pumped through a hose to the point of application where it is sprayed in a tight pattern by use of air pressure from a nozzle having a 3/8" to 1/2" diameter orifice onto the surface to be fireproofed. This vet material then sets to a hard plaster having a density of 20 pounds per cubic foot. Likewise because this vet material is up to three times heavier than the vet spray-applied asbestos fireproofing, any overspray or rebound does not bee airborne -3- 7S<34> E but falls to the floor and hardens. \ Attached are photographs showing the application of plaster fireproofing. (Exhibit 3) In this regard we would like to call attention to the "Background Information -- Proposed National Emissions Standards for Hazardous Air Pollutants" published by EPA in December, 1971 (EPA Background Information). On page 7 it is stated that: "The proposed ban on the spray application of products that contain asbestos Is based upon experience with spray-fireprocfing operations wherein efforts to control emissions by the use of containment and good housekeeping practices have repeatedly failed." It Is our belief that the above statement refers to spray-applied asbestos fireproofing usrsee7 'i^Ibi^'A) u- reason for our belief is that the rebound and overspray from plaster fireproofing lend themselves to good housekeeping methods because the hardened overspray can* simply be gathered into a pile for proper disposal. --v V A more concise ppmoarison of spray-applied -asbestos \ \. . T .. u . /[, ./V fireproofing and plaster fireproofing is''aatftcai ched to this \ V \' \j statement as Exhibit C. - / /\ ___________ -_____ ________ ASBESTOS FIBER EMISSIONS FROM PLASTER FIREPROOFING On the same day that EPA published its proposed -4- "7^06? f National Emissions Standards for Hazardous Air Pollutants, there appeared in the Federal Register an emergency standard for exposure to asbestos dust published by the Department of Labor pursuant to the Occupational Safety and Health Act of 1970 ("OSHA"). This standard which is Section 1910.93a states in part: "The 8-hour time-weighted average airborne concentration of asbestos dust to which employees are exposed shall not exceed 5 fibers per milliliter greater than 5 microns in length, as determined by the membr2nce filter method at 400-^50 X magnification (4 millimeter objective) phase contrast illumination." In order to deter mine concentrations of airborne asbestos fibers during and after the application of plaster fireproofing in the fire proofing of structural steel, observations were made at three construction sites in the San Francisco, California area on May 26, May 28, and June 4, 1970., Consideration was given to the actual and potential exposure of (a) workmen carrying out the spray operation, (b) workers in allied trades nearby, and (c) the general public. These observa tions were made by the highly respected Tabershaw-Cooper Associates and a report of their air sampling findings appears as Exhibit methods of asbestos fiber detection recommended by Section 1910.93a of the OSHA emergency standard for exposure to asbestos dust quoted above were employed. _ 5- -/ "7 % Cr The Tabershaw-Cooper observations indicated that the occupational exposures to workmen who were operating the spray nozzles applying plaster fireproofing were net above the recommended threshold limit values for asbestos published in Section 1910.93a. In fact, of the numerous samples taker., only one sample higher than this level was found. Concentra tions dropped off rapidly in the adjacent areas. Tabershav;Cooper reported that expressed uniformly as fibers per liter, exposures of spray crews in all except the one case mentioned above were well below the threshold limit values; workers in adjacent areas of the same buildings were exposed to concen trations from 1/10 to 1/5000 of this value; individuals on other floors of the buildings and in the building vicinities had transitory exposures ranging from 1/100 to 1/5000 of the threshold limit value, ambient air levels in the Bay Area were from 1/500 to less than 1/5000 of this value. In addition, Grace itself has taken similar asbestos fiber detection observations at construction sites where plaster fireproofing was being applied. These observations were taken during July and September 1970 at Omaha, Nebraska; Bethpage, New York; and here in Los Angeles, California, using the same recommended membranee filter method. Samples from these locations were analyzed for Grace by Werby Laboratories Inc. of Boston, Massachusetts. The results are att ache d. (r1 (Exhibit"!) 6- 1- ,. 7$0c* H A review of these results clearly shows that in all cases the fiber counts were considerably below the threshold limit values for asbestos established pursuant to CSHA. We would like to further point out that the fiber count data in the Werby analysis consists of a^l fibers and is not limited to asbestos alone. In your proposed "National Emission Standards for Asbestos", Section 61.22(e)(3), it is stated that fibers may be emitted to outside air if a fabric filter of the type described in Section 61.23(d) is in use. We have been advised that this filter would limit fibers' emissions to the atmosphere to approximately 0.5 to 1.5 fibers greater s than 5 microns in length per milliliter of air sampled. You will note that in both the Tabershaw-Cooper and the Werby , SvorWO'****'*^ findings set out in Exhibits D and E,JMall observations corresponding to outside air sampling are below the fabric filter standards_and this in cases where no filters were in use. As to the question of whether or not there are fiber emissions of asbestos from plaster fireproofing after it has been put in place, we would like to refer you to an analysis of air samples taken by Tabershaw-Cooper Associates at the request of the Bechtel Corp. in San Francisco in September, 1970, in which it is concluded: -7- iso&z "The conclusion of the above test program was that the maximum concentrations of asbestos fibers found in the sampling locations were approximately 2 1/2 fibers per liter. As a comparison reference, the normal atmospheric concentration of fibers in the Bay Area varies from 0 to 10 fibers per liter. ''Based upon the enclosed report the concentrations of asbestos fibers in your building are on the low side of the normal ambient concentrations found throughout the Bay Area." This report upon which the conclusion is based is attached to this statement as Exhibit F. As to the durability of plaster fireproofing, you will note in a test performed by the Boyle Engineering Laboratory for us in April, 1964, plaster fireproofing was exposed to a high velocity air stream (over 100 miles per hour) for 87 consecutive hours and no erosion occurred. A report of this test is attached as Exhibit G. AVAILABLE SUBSTITUTES In the ,EPA Background Information it is stated that asbestos-free substitute materials are available for sprayed asbestos fireproofing for a cost no higher than 15? of asbestos-containing fireproofing materials. Grace does net deny that such materials are available. In fact, Grace itself manufactures and sells substitute materials. However, Grace wishes to point out to you that at least as of this date none - 8- r ~7S"3iT of the nor.asbestos fireproofing materials approved by Underwriters' Laboratories, Inc. have achieved full equivalency with the asbestos-containing materials previously approved by UL. The area where full equivalency has not been obtained is in the ability of the nonasbestos-containing fireproofing materials of the types here under discussion to remain in place during fire exposure as long as the asbestos-containing materials. This bonding ability is an essential parameter of these types of fireproofing products. In our judgment, the ability of the asbestos-containing materials to bond to the structure for a longer period of time than the nonasbestcscontaining materials gives asbestos-containing materials a certain margin of safety which even if only once required, would be worth their use. At this time we and others are in the process of experimenting with, and researching for, materials which will be fully equivalent to the present asbestos-containing fireproof materials, but having even less asbestos emissions and in some cases no asbestos emissions. Grace's efforts will continue until such time as fully equivalent new plaster type materials are developed. -9- *7 5 3 GZNEPA1 C3SEPVATI0N Earlier in this statement Grace alluded to the broad scope of the proposed National Emission Standards and in this connection Grace would like at this time to make a general observation. The aim of the proposed standards, as they concern asbestos, is to control the level of asbestos emissions. Emission limits are specified for the numerous uses and applications of asbestos. We feel that E?A activities in this are appropriate. However, we feel strongly that the absolute prohibition of spray application of "any product which contains asbestos" is arbitrarily severe and inconsistent with the objectives of E?A. This is because the proposed regulation would prohibit materials otherwise acceptable simply because they contain asbestos, even though the use of the material would result in airborne asbestos far below the level acceptable for all other products formulated with asbestos. Moreover, by specifying "asbestos" instead of "commercial asbestos", the regulation could even be interpreted as prohibiting the spraying of materials containing minute traces or stray amounts of asbestos. -10- 7 5^ We feel that it is not the intention of EPA to establis a standard so arbitrarily severe. We believe the regulation was written in its proposed fern because of the failure to differentiate between spray-applied asbestos fireproofing an plaster fireproofing. conclusion Grace recognises and approves of the general desire to limit asbestos fibers in the ambient air. This desire shcul be weighed in each instance against the benefit to be gained by prohibiting a specific activity. In our Judgment, the benefit to be gained by prohibiting the use of plaster fireproofing is r.ot commensurate with the continued benefits to the public in having a plaster fireproofing containing asbestos available for use. Especially is this so in a context where there is no data that defines the excess risk, if any, to the public from exposure to asbestos fibers in ambient air and where asbestos fiber emissions attributable to the use of plaster fireproofing are in our Judgment less than the point of references presently established by EPA an OSKA. Accordingly, Grace hereby proposes the following modification to Subpart 3 - National Emission Standards for Asbestos : "A new subparagraph (n) shall be added to Section 61.21 as follows: "(n)" 'Plaster fireproofing' means any direct-to-steel fipeprocfing product containing less than 12:1 asbestos 7 SOC, *\ by weight which is mixed, pumped and spray-applied in slurry form and vich after application hardens into a plaster with a density of 18 lbs. per cubic foot or more. " i Sections 61.22(e)(1) and 61.22(e)(2) shall be modified by deleting the phrase': "The spraying of any product which contains asbestos" and inserting in lieu thereof in each case the phrase: "The spraying of any product, except plaster fire proofing, which contains commercial asbestos." Section 6i.22(e)(-3) shall be modified by deleting the phrase: "Emissions of particulate matter from spraying of any product which contains asbestos." and inserting in lieu thereof the phrase: "Emissions of particulate matter from spraying of any product, except plaster fireproofing, which contains commercial asbestos." We wish to thank you for the opportunity you have given us to sake our views known. If there is any other informa tion which you may require, we will be pleased to provide it. rv 3/72 -12- *7 S 0 !c fv 1 f/\t i' V 1l f i 1 I I kI r r i } ih.o iJ . HI *7 5Z>(e O i ii! I* \ fI i* / ii l \ t \ ! i i c_ ccS- c Sc- c. <i j i JIXJl I1JIT Ic i It 4tI4 f c L J c: r tt i i \ t \ i t I i} l i L K X IIin iT 13 fllx lii,' p la r.L c r f l re p ro o f Inr, lnt.o I 2.^ \ i i I i r f If ii .4 ti \ "\A i i tMt m3 r VII T riT T H I I I I t <I. J; I *f ' it t a f \ It i F .xm niT $ I ii I i ( i i * \ ! i i i L1 4 7> I I 1 -- /, ;v / r. i .\ I ) A i- . -s . *. 4 .A A4 'i i -4 1t i K X IIIIJIT n 7 Z -is V/' EXHIBIT C PLASTER FIREPROOFING V. SPRAY-APPLIED ASBESTOS FIREPROOFING (1) Formulation (dry ingredients) Plaster Max 12% asbestos by weight Sprayed Fiber approximately 33% asbestos by weight (2) Mixing (ooening bag) (Mixer) dry ingredients dumped into hopper containing water (additional water added as needed) mixer forms wet plaster dumped into hopper (dry) no water added mixer fluffs dry material (3) Pumnine (4) Spraying wet slurry pumped slurry sprayed wet (under directional air pressure) dry ingredients blown \ dry spray w/small amounts of water to mix with dry fibers at nozzie en (5) Waste overspray and/or rebound is in "wet" condition sets to hard plaster fibers from overspray become airborne when dry upon drying, easily swept or blown away (6) In-Place (drying) sets to hard plaster consistency (20 lbs. per cu. ft.) passes 100 mph air erosion test light density (7-15 lbs. per cu. ft.) remains relatively loose and soft EXHIBIT C PLASTER FIREPROOFING V. SPRAY-APPLIED ASBESTOS FIREPROOFING (1) Formulation (dry ingredients) Plaster Max 12% asbestos by weight Sprayed Fiber approximately 33% asbestos by weight (2) Mixing (opening bag) (Mixer) dry ingredients dumped into hopper containing water (additional water added as needed) mixer forms wet plaster dumped into hopper (dry) no water added mixer fluffs dry material (3) Pumping (4) Soraving wet slurry pumped slurry sprayed wet (under directional air pressure) dry ingredients blown u dry spray w/small amounts of water to mix with dry fibers at nozzle end (5) Waste overspray and/or rebound is in "wet" condition sets to hard plaster fibers from over spray, become airborne when dry upon drying, easily swept or blown away (6) In-Place (drying) sets to hard plaster consistency (20 lbs. per cu. ft.) passes 100 mph air erosion test light density (7-15 lbs. per cu. ft.) remains relatively loose and soft .Spray-Applied Asbestos Fireproofing :Plaster Fireproofing Containing Assestos j{ PLASTER MIXER PIASTER PUMP AT NOZZLE m.*' P*M <-'l" ZONOLITE CONSTRUCTION PRODUCTS DIVISION TT"? T 7-^5- Excerpts From Tabershav-Cooper Associates Report Dated July 15, 1970 / ASBESTOS FIBER CONCENTRATION'S IN' AIR FROM SPRAY FIREPROOFING OPERATIONS USING ZONOLITE PRODUCTS In order to determine concentrations of airborne asbestos during and after the application of vermiculite-asbestos cement materials in the fire proofing of structural steel, observations were made at three construction sites in San Francisco on May 26, May 28 and June 4, 1970. Consideration was given to the actual and potential exposures of (a) workmen carrying out the spray operation, (b) workers in allied trades nearby, and (c) the general public. Sites studied. Three spray operations were surveyed: (1) the Embarcadero Center, where Mr. G. Connell was spray contractor; (2) the P.G. and E. Headquarters Building, where the spray contractor was C & R Plastering, Inc. (Mr. Rasmussen); and (3) the Hilton Towers, where Mr. G. Connell was also the contractor. Methods. Airborne fiber concentrations were determined by drawing air through Millipore type AA filters, with 0.8u mean pore size. Samples were taken in the breathing zones (Bz) of men working with the material and at various locations surrounding the operations. Air flows ranged from 0.11 cubic feet per minute (cfm) in breathing zones to 1.8 efm in areas more distant. Portions of the filters were mounted on slides, and the fibers in 100 microscopic fields counted, using phase contrast microscopy at a magnification of 430x. The numbers of asbestos fibers seen were converted to concentrations, expressed in fibers per milliliter of air, by taking into account the area counted, the flow rate, and the sampling time. S DATA FROM TA2EESHAW-COOPER ASSOCIATES E-3ARCADERO CEETER AIR SAMPLES (5/26/70) Area Asbestos Eibers Total f/rl f/r! (>5u> Spray operator's "breathing zcne Spray operator's breathing zor.e Spray operator's breathing zone (held near bach of head to nrotect face of filter) " Stage rover's breathing zone Area near spray (1-50 ft. distant, sane direct spray on filter) Background area, 43rd floor (air flov post spray-encrusted drapes) Investigator's breathing zone Mixing operator's breathing zone 7.96 2.63 3.56 1.86 0.030 0.020 0.79 0.775 6.54 2.18 3.18 1.55 '/ 0.028 0.016 0.60 0.710 7 $ C<c ** DATA FROM TABERSHAW-COOPER ASSOCIATES PG 4 E BUILDr^G AIR SAMPLES (5/28/70) Ares ! Sprey operator's 32 Spray operator's 3Z BZ of investigator, close to spray stage, valuing vith hod-carrier Area, 4o feet rewind of single stage (air flow variable) Area, - ho feet downwind of stage (air flow variable) Mixing operator's BZ (wind away fron) Mixing operator's BZ (wind toward) Mixing area (between two nixing operators) Mixing area (between two nixing operators) Background, 1 floor below spray operations, most air flow not through the building to filter, but variable. Area, between two stages (current to pmp cut off at variable tines, total flow through filter uncertain) Area, 30 feet frea stages (2) Area, 35 feet frea stage, (air flow in area uncertain and variable) Asbestos Fibers Total f/nl f/nl (> 5 u) 3.32 2.91 3-15 2.64 0.16 0.14 0.13 0.11 0.25 0.23 0.50 0.42 1.1*2 1.09 1.34 0.014 1.25 O.98 l.l4 o.on 0.038 0.071 O.36 0.036 0.061 0.34 7 S' Cf DATA ISOM TA3ZP.SSW-C00PSI ASSOCIALS HUTCH TCTOS A3 SAMPLES (6/4/70) Area ; Spray operator's BZ Hod Carrier's BZ Upwind of stage Downwind of stage Upwind of 35th floor - Background (Prob. non-iso-kinetic flow at filter face; validity as a final neasure of fiber background level?) Downwind of 17th floor (four floors below spray operators) Mixing operator's BZ Mixing operator's BZ Mixing Area Asbostos Fibers Total f/r,l f/sl (> 5 u) 2.W 2.20 0.U9 0.33 0.0007 0.0007 0.011*7 0.0137 none seen none seen 0.0017 0.0017 1.61 0.55 0.U3 1.1*5 0.50 0.38 WlU70^ ; fviLILT t AMBIENT AIR SAMPLING RESULTS' DATA OBTAINED BY TAKERSHAW-COOPER ASSOC. \ (FIBERS/ML) Up- Sensiv/ i n d t i v i t v Morn i n a StatTy, 0.024. 0.005 Moving 0.014 0.005 Down- Sensiv/ i n d t i v i t v 0.015 0.016 0.042 0.00S Afternoon StatT y. 0.077 0.0OS Moving 0.00S 0.0C5 0.015 0.005 0.005 0.005 A IR FiBER CONTENT MEASUREMENTS ON MONO-XOTE THE "MEM3RANE FILTER METHOD OF ATMOSPHERIC SAMPLING" WAS EMPLOYED FIRST NATIONAL - OMAHA, 10th FLOOR AREA. FIBERS OVER 5 Micron/cc Spray, 1 - 3 T Overhead and Vertical Mix Outside 0.7 0.9 1.1 i'it's:; / I C//// L A C C R A TORIES I C f/ it s u /1 i n ~ n r, d A n n I y t i r r l C h < ut iris ti C . 7 '0te> It trw<J $# UiUa to M vdiicMi J.0/3t July 16, 1970 Samples of : 37 KM. MEMBRANE FILTERS Marked : FOR MICROSCOPIC ANALYSES (Phase Contrast Method at 4 30X) Submitted by : Construction Products Division W.R.Grace & Co. Catnbr ideje, Massachusetts 02140 Note: Values Reported Are Based U n an Assumed. Equal to 180,600 CC. t W* ^w *. SAMPLE MARKED FN *11 FN r, 2 FN #3 TOTAL FIBERS PER CC. 1.1 ' 1.2 1.4 FIBERS GREATER THAN 5 MICRONS PER CC. 0.7 0.9 1.1 AIR FIBER CONTENT MEASUREMENTS ON MONO-KOTE THE "MEMBRANE FILTER METHOD OF ATMOSPHERIC SAMPLING" WAS EMPLOYED GRUMMAN AIRCRAFTS DATA PROCESSING RESEARCH CENTER IN BETKPAGE, N.Y. \ L 0 \ i i o 3 j , AREA Spray, 10* Overhead Spray, 3* Overhead Mix General Area FIBERS OVER 5 Micron/cc 2.6 1.1 1.3 0.4 !/\ /y1^i jr I LABORATORIES INC. ; J Consulting and Analytical Chemists 7 b/--V^" / ' U' li 10 M i ( h * 11 llktriy J.073t July 16, 1970 Samples of : 37 MM. MEMBRANE FILTERS Marked : FOR MICROSCOPIC ANALYSES (Phase Contrast Method at 42CX) Submitted by : Construction Products Division W. R. Grace & Co. Cambridge, Massachusetts 02140 Note: Values reported are based upon an assumed sampling volume equal to ISC.,000 CC. SAM?US MARKED L. I. # 1 H- I. # 2 3If. I. # 4L. I. # TOTAL FIBERS PER CC. 5.7 1.4 1.8 0.4 FI3ERS GREATER THAN 5 MICRONS PER CC. 2.6 1.1 1.3 0.4 r- A B O n A T o I il ; jtv rm- i C o n s u 11 i n ff a n d A it n ! y t it: u l Che in i s I s 7 `TOC, U 16 !* tO tlktHf ? 073* SeptGTi'c21" 20, 1970 Samples of : 37 KM. MEMBRANE FILTERS Marked : For Microscopic Analyses (Phase Contrast Method at 4 2CN) Submitted by : Construction Products Division W. R. Grace & Co. 62 VThittemore Ave. Cambridge, Ma ss. 02140 SAMPLE MARKED TOTAL FIBERS PER CC. L.A. - 8 (M-K Spray Operation) L.Ao - 9 (M-K Mixer Operation) L.A. - 10 (M-K Mixer Operation at Convention Center) L.A. - 11 (M-K Spnay at Nozzle, Convention Center) 2.0 1.9* 1.4 1.1 FIEERS CPEATER THAN 5 MICRONS PER CC. 1.1 0.7 , 0.8 0.5 *- it t ,V. 1 . ,, l \.o . ' _ ..'-i.4 lr::.r'a:'-r.-j ir.cc i-nG!::r:;.r:ArTP""T nAIt r f';.'-.i\-wl3C0, CA : r* 0/ (*. ir.) 2t?-:.::0 3n-anTj. corporation' NO )'.:a3e .'llreel San Francisco, California a vi -Jrr ` W*T T< rv t. 1` 11 v i v V' J \ 1 im* J rOn**^**'4^^!7*'1*: September 3, 3.270 l:ilc No. i! 13:2 -i: 1 Report No. 17 3 2 : an a :.yt is or atr r.:.i:S. r.rniY:-u buii.cing r; t/> have evaluated the cc:'.c::;tr;:;io::s cf fibers in the Fifty Beale Street Et:ilain. The objective investigation arc as follows: Betorr.ir.e r.iic ccncc-ntration cf asbestos fibe ~s in a typical v/orh area. Determine if these fibers i * W V*'*.^*.***r*.*^ * i Vi'l outside sources cr inside sources. Provide initial measurements of fiber background counts . Provide initial measurements ox fiber erosion, fror.i the air plenums spaces. r'.-firr discussions Kith your personnel and review of the duct system ..:r.yo-:i, the following locations were sampled. 1.. Building roof, Nest side 30th story level. *> Outsidc;i.hir supply entry, 14th floor Mechanical Room. 3. Behind the air supply filters, 14th floor Mechanical Room. .4, Air duct, Room A-13 16th floor. S. Return air duct to 14th floor Mechanical Room. i.iils of the enact sampling location, particle analysis, arn _c:.i:3ts arc presented in the enclosed repost fro:;; out consult, i anersii:-.k- coopc r Assoc: arcs . 1^0 h c CO n c 3 u r ior. of the ah o VC test pro^r as .that the r.n.\ii.;u::i cento r;i1[j 0 nr of eb c s t 05 f i. b c rs found in t e rar.pl j n;, locations uas ; pr i n r.:: e J / 2 A f i be rs per lit. c r. As a CO)- .'.risen re fe rer re , the ::on::l atr.c:;,:boric ccnce ntrn ticn of fibers in Lhc Hay Area verier, fron 0 t fJ be; p e r l iter. Bayeu upon the- enclosed report the cor.ccr.trr.t it '! s o f e s b c r. t o r. fiber: in your bulletin'; ere on the lot: side of the no: ar.bicr.: concert:- tiers found throughout the Bey Area. AbhOT A. I!A.,:.::S YI-cVlhG LAB0.T0I-.IE5 ^ /,/S,', *1 <\ / , V * <W W y L# < lTl 1 cc: (6) u/cnclosures t PAG". Th'u r. 7+ D, Cs.:;*'. ! J\ . /. a- //i 't ' V" V*^r > <' / -'/ ' ^ * v-- '<***'*.'+ * . . 2ir.:- r.:ivr. r.n.-zcT. c-.r:;rL:y. c.*-n.-,?ci AI/Wt/Au .#.* ^J* 2 /< Tc\;* -- (<:\ ( = : DAT3: September 1, 1970 TO: from: Abbot A. Har.hs ,/ Tabcrshav-Cooper Associates PE: Analysis of air samples collected i n t h c I' c c h *. c 1 Corporation headquarters building , Sar. T: and sec, California. During the period July 6 to 13 1570 r s ar ^ -L ^ c taken at several points vi i n . i r r. o vi ng cyst c:i Dear. wc 1 3u 1.1 a j.u , 50 o c alo 3 tr f: et : 1 a n 7 r an c i SCO, Cali The purpose vas to determine & 2 Ls z c - f i'oe r s vc r c- b added to the moving air stre in i* S pas s are over asshofcs.es- containing sprayed fireproof icter: a_ c* mi fir cpr Wm, *C .** -% .*. . material (a cementitious typ c , supp, .ied y lo noli t e 'u of U.R. C-race) had teen appl ied to ; struct ur El ctec i :z of the buildinr during construe ties j a e c u t lo G6. Contact s the moving air ctrear. vith the fireproofi * * L> " atari to thct space "between the struct urtl and s us pc r. d c d c cal - o each floor of the building; thi ! y^ ^J ace is use d as th c air return f:dust." Air scr.plcs vers taher. at fov. r locations vithir. the ai strcaa supplied to, and returned f ror., the occupied reens o the 13th and Ibth floors of the bu aiding, and frem a locati on the roof of the build-nc* The sampling locations vere: (1) Or. the vest edge of the buildi ng roof at the 30th story level; (2) at the supply entry to the 13th and 1^th floor ventilation syster., on the northvc st corner of thcl^th floo (3) on the dovnstrear. side of the filter through yhich the mired recirculated (7*5^ ) and outsi dc (25?) air vas passed before entering the ventilation sy stem; (1*) at the supply duct outlet in rocs A-13; (5) at t he duct through vhich the accumulated return air from the 13 th and l^th floors vas returned to the* i^th floor r.echani cal room for eventual die charge or recirculation. Figure 1 shovs (schematically) th campling locations. f BECHTEL BLDG . 14th FLOOR  3> - -c- Gr.nrl 'l:ir r.d A nn) v r. : All Ecnpit.'; vcrc oxen r c.v i n(". `-i r eh ro v. ph I i 2 1: - c : f. r. n Jr. ill* = . 1. 7 r.: in ii'o-.c.iT, v;',;, 0 . c. I'i c* r* at n. fir v rate of 0.0 c ubiu fee*- per i r. v.t c . filter holders ve re pic c 2 in the moving rnr streams t.*. vh ere the lincc-r nr'' eir velocities r-i matched the .he filter face V c. rooftop campisnc static:: vas faced into the prevail!nr vcstcrly vind. Air oar.pl es vcrc talcn daily r.t each location dvr in;; tvo tiro periods: 10:00 A. 1j - to 2:00 sample:)', car.p.lc vcl- 2'.0 cubic feet or oVpO liters or 6.79 cubic raters; ar.d 0:02 to 9:00 A.::. o a.v.ple ) , 3t'> cutis feet or 10,-271 utter:, . C . C 7 c u e c .voters ^;:ccp v :cr.5 vorc 7.:: c an e last d. : J v r.r.-.plir.p; on the forr.er (July c) only sample vas taler., on tiro letter (July 13) only o A.. r.-~- e vr.s taler.. Analysis of the dust sarnies collected or. the membrane c> (/> liters vas by the r.ethcd recommended by the United ublic health Service for th.a* deter:.*.in:.t ion of asles /* A portion of the rentrr.ne filter vas placed or. a microscope V slide, cleared by the addition of a drop of a mounting T.rdiv.r. match;:','; the index of refraction of the filter, r.r.d covered v 11 :i a : o v e r slip htc mounted filter vas then examined vith phase contrast microscopy at a magnification cf HO rancor. microscopic fields (defined 'ey a Porton eyepiece reticle) vere so examined, and all fibers counted and placed in size cstcy:ries. The location of each fiber vas marled, and the slide vr.s transferred to .the petrographic microscope, vhere (also at a. r. a r. i f i c r. t: or. of 13 C .1) the fibers vere i d c n t i fiec. The identification ir. this ease vas limited to deciding vhether or r,ot the fiber in question vas asbestos. The num bers of asbestos fibers seen vere converted to concentrations, expressed in fibers per liter of sampled air, by tahin into account the area counted, the flov rate, and the sampling time. A cecondary analysis vas the determination of the crr.vinetric concentrations of ail particulate matter. The filters vere veifhed (0.C02 ~Z) before and after exposure; the change in veiut vas divided by the number of cubic meters of air vhich had passed through the filters, and the results exp re s c c a as r.icrcrrar.s o S* aA rtic uiate' ; c r cue; Re r. v\ t ? rc:uM:; of the :.ir cr.n^llrj; preyrar. arc i c 0 11 y . .. -- ~j ... J. , and ::;;c V:'. ........ ' nc: >J. - 7 * 7 < -- - ,, - c. n c Tiic tvo tul'::. fcr each z I'.r.y 11:.:; location in Tab]'.- I v , the - 1- c z t o s iL bcr cor. - eat rnt: on curing the c 7.0 c J. fi e d 7 . 0 period::, foil u v c d by the g c 7 ri c. concentration of total p art- i c u.l at c r. . Figures 2 end 3 shev tie r o r. c n nnd.roccr.s c 7 the asbestos and total particulate concentrations.. Disc*.:.*, .tier. cf Pc suite rj ,0 The concentrations of asbestos fiber a and to; cl part dilates four.;; at all points vita ir. eh i 0 rye ter. are v i t h i r. the ran pc vc have core to cr.pcet ae "r. or.:, al" in c:: tens! ve st udier. of asbestos fiber content of r.r.b:. cr.t air in the 1 Area. This range in usually ire:: 0 to 11 fibers per line lthcugh concentration:-. a: hi g r t-m'0 fiber;; per .liter ha ten found-in fan Francisco. r~ \ If fireproofing voro contributing markedly to the. parti culate burden cf the noving air stream, one vouid err.c.ct that air after passage through the syr-ten vould contain r.cre asbestos fitcrc ac rcluted to total part eulat e s:n: than veuid ar.blc.nt or poet-filter air. Ever, hours. the l'irenr sc f i a, is of lov ash. or tee content (5--0r), it is still relatively ric in asbestos coopered to other structural elements of the building and most cor.:.:uni ty sources of airborne particulates. The absence of such a differential increase surest; that ".he fireproofing in the building vus net a major contributor to dust in the air stream. Asbestos fiber concentrations in the return air ct re an. correlated poorly vith rrsvisctric concentrations cf total partieulates (.fig. ^) . Therefore the relatively simple pro cedure for measuring total particulate burden cannot be used ac an indicator of asbestos coneer.tr at ion. r \ Roof A ir E ntry A ir filte r e d A ir Peon A-13 O utlc B e c h te l B u ild in g - A sbestos F ib e r C o n c e n tra tio n s ir\ o IA oft t-v CM H H o o - c ; 7 r/ -^ o c 7 j it Poof E ntry F ilte re d l!oo;: A -13 A ir A ir A ir B e ch te l B u ild in g - iO u .l P a rtic u la te C o n ce n tra tio n s / jr yir.: >'i r> O K tJ C(J CJ u A ir 0 0 CVI O VJ H O CVJ H O S3 ~711 in^cr.3 37qr.r>/ cu:\7.: 2 c2 7 ; , U t, * ^ J * * t, s' ^ u -r-< ;3 < O f:; 1 to c ' < P H O P JZ O O - e 0 H P an uc +* H z i) 0 /4 z .j c r: 00 u >4 00 P0 rl <r-> V 4* na O *< +> n 0u O P n s0 Pi c* 0H C c 40 O r-f -> a m* O0 Vi Vi O O -Tv az>; 7-/cr;c7 j :o;:oqr*i oco vp o c-i o Cone .1 v r 1 o -i The c o r. co^.retl c r. r. o T nil tome a r, - c r. i o r in the r.ir r.v.rr.iy ard return cT .ho : c.re at the lov* end of the rar.^e of cc:: e c ::t ;: out z i cc air . < id ir. Report Prepared By: J. LcP.oy liaincr, M.S. Dougina*?. Pooler, M.S. 9/1/70