Document mmong6XLjr8GkeGGvkKmZOO7d

FILE NAME: Union Carbide (UC) DATE: 1973 Mar 9 DOC#: UC222 DOCUMENT DESCRIPTION: Internal Report - The Safe Use of 'Calidria' RG-244 in Corrosion Resistant Tank Fabrication with Cover Memo Letter to Dow Chemical P-C: d. L. Myers File UNION CARBIQt CORPORATION MINING 8 METALS DIVISION P.0 BOX S79 I t DISCOVERT COMPANY NIAGARA FALLS. H. T. 14302 T il; 716-278-3375 Marc. 9 , 1973 Mr. E. T. Shallow Dow Chemical Comoany Designed Products Division 2040 B uilding Midland, Michigan 48640 Dear Mr. Shallow: In accordance w ith our telephone conversation o f March 8 , 1973 a copy o f "The Safe Use of 'C a l i d n a 1 RG-244" th a t has been passed througn our legal department is enclosed. This one also in clu d es th e th re e ta b le s th a t were om itted previously. u u . * have no objection to your re w rite man d e le tin g f u r th e r p o rtio n s, we should, however, discuss h is fin a l r e s u lt with o ur a tto rn e y s before p u b lic a tio n . This can be done by telephone i f necessary* Very tru ly y o u rs , fi). H. B. Rhodes ^ Area Manager Marketing & Technology HBRrcjb Enclosure A08S2b THE SAFE USE OF "CALIDRIA" RG-244 IN CORROSION RESISTANT TANK FABRICATION * 1. Introduction Asbestc- has received a g reat deal o f a tte n tio n and p u b lic ity in the l a s t several years and has becomme the f i r s t substance covered by new OSHA h ealth re g u la tio n s. U nfortunately, much of the media treatm ent o f the s u b je c t has been em otionally o rien ted and d is to rte d and in some cases has bordered on the sen sa tio n al and untrue. Many users o f asbestos and products containing asbestos have been m islead regarding th e s a fe ty of asbestos and what is needed to comply with the OSHA requirem ents. * . . I t is accepted th a t a sb e sto s, lik e many o th e r foreign b o d ie s, can cause d isa b lin g lung damage which fo r asbestos is commonly re fe rre d to as a s b e s to s is . I t i s im portant to n o te , however, th a t a sb e sto sis and s t a t i s t i c a l excess occurrences o f bronchogenic carcinoma (lung c a n c e r), th e two most comnon a sb e sto sre la te d d iseases, have occurred only in workers with long-term exposures to massive concentrations o f asbestos d u st. The ris k o f th is type o f exposure is usu ally in asbestos mines and m ills and in la rg e manufacturing o perations th a t use q u a n titie s such as 20,000-30,000 pounds p er day. Long-term, massive exposures a re , of course, not typical of polyester tank manufacturing operations u tiliz in g RG-244 where a t most a few bags are used per day. Much has also appeared in the pu b lic press regarding the re la tio n s h ip between asbestos and mesothelioma, a rare type o f cancer o f the p le u ra . In almost a ll cases where th ere is a strong s t a t i s t i c a l re la tio n sh ip between mesothelioma and the in h a la tio n of asb esto s, c ro c id o lite and/or amosite have been involved. Where asbestos exposure has been lim ited to c h ry s o tile asbestos (RG-244 is c h ry s o tile ) th e re is stro n g evidence th a t no excess mesotheliomas w ill occur. 2. OSHA Regulations _ A fter extensive h e a rin g s, a new standard fo r Exposure to Asbestos Dust was published in the Federal R e g iste r, Volume 37 No. 110 on Wednesday, June 7, 1972. The b asic exposure standard is an 8-hour time-weighted average (TWA) of 5 .f i b e r s . longer than 5 m icrom eters, per cubic centerm eter o f a i r . The f ib e r lim it is to be reduced to 2 on July 1, 1976. A peak co n cen tratio n o f 10 fib e rs per c c . , longer than S micometers is not to be exceeded a t any tim e. Note p a r tic u la r ly the use o f the time-weighted average over th e 8-hour s h i f t . An op erato r perform ing one or two s h o rt additions of RG-244 per s h i f t , as is ty p ical o f p o ly e ste r tank m anufacturers, would have h is exposure du rin g th is dumping time averaged w ith zero (o r a low-background le v e l) fo r the r e s t of the s h i f t . I t is im portant th a t th is concept be understood fo r in te rp re tin g the effe ct of interm ittent exposures. Improper in te rp re ta tio n of th e reg u latio n s has created many miscon ceptions about the equipment and procedures needed to "se a sb rsto s. I f exposure lim its u,e not exceeded, the main fu rth e r compliance requirement is medical exam inations. Medical examinations are required fo r a ll employees in any &08826 "occupation exposed to airborne concentrations o f asbestos f ib e r s ." Some d e fin itio n of "exposed" is necessary sin ce evidence in d ic a te s th a t small amounts o f asbestos fib e r have existed in the atmosphere f6 r m illions o f y e ars. The source o f-th ese fib e rs would be from the w eathering of n a tu ra lly occurring su rface outcrops. In te rp re te d l i t e r a l l y , the re g u la tio n would require physical exannnations fo r everyone in in d u stry . In i t s c r i t e r i a document on a sb e sto s, fuosh recommended th a t exposed to a sb e sto s11 be defined as "average exposures above one fib e r p -- cc. or peak exposures above fiv e fiu e rs per cc." 3. ^ C alid ria" RG-244 in P o ly ester Resin ^Uf 1n9 ^a s t six months, a major asbestos m anufacturer has made h dust 0 ^ measurements a t eig h t major p o ly e ster processing p la n ts. a i S0 b?en ?*de d u rin 9 sanding and grin d in g o f p a rts produced ITM Uf . reS1n- In cases, sampling and counting were done with the equipment and techniques p rescrib ed in the OSHA re g u la tio n s. M H at ainht f dus* counts taken in the breathing zone of the operator a t e ig h t m anufacturing lo catio n s are shown in Table I . Samples were c o lle c te d ?notnTUA?e f ? S ln9 r t h e b a 9* o f rg"244 and re p re se n t c e ilin g con cen tratio n aih ictlic / c S e iP co?n t s * Examination o f the data shows th a t in a ll cases the ffiibbeers/c/ccc*.*?>?5* tpnrelslcri-bKerd! ifna rthbee lOTMSHA? *re ganuolawtiaobnles. c e llin g co n cen tratio n o f 10 so th a t thii0^ . ! P e r at or Takes on1y one sudl dun>P in hl`s 8-hour s h i f t f?ndino h5c k V *e2 i ! hown WOu1d be av eraged With much lower values in w e r f exo2sedt t r t h ! 1^ t Kd` J Vr a9? 1TMA) exposure* For example, i f the o p erato r as one ha i f l evel found* K e ` * 2 ' 8 f i b e r s / c c . , fo r even as much l i 9 the dump1ng o ceratio n and to a background level o f 0.5 wf S c- for seven and one h a lf hours o f h is s h i f t , his tim e- weighted average would be: TWA - iO-S) (2. 8) + (7.5) (0.51 8 0.7 fib e rs/c c . >% 5e I ? ' 5 ? 2 u t ! ! V ur re n t 5 f ib e rs /c c . and the 1976 level o f 2 f ib e rs /c c . and the NIOSH d e fin itio n of "exposure to a sb e s to s." * Tbe OSHAregulations p re scrib e sp ec ia l p recau tio n s fo r th e d isp o sal h lJm H bags and containers i f in any reasonable fo reseeab le use and handling d u st le v els above the allow able lim its w ill be g en erated . In two of tne p la n t su rv e y s, d u st counts were made during the handling o f the empty RG-244 fl=9w ifJ 5 S ra s u lts given in Table II show lev els well below th e OSHA lim its . ''I 9 ? a t ? 91ven Pre v i u s ly , these values were obtained during a^ l* handling o f the bags and would re p re se n t peak ra th e r than tim e-weighted average exposure. 3 "^e da ta Presented in Table I and II are f o r p o ly e s te r manufacturing u j S should re p re se n t much more severe co n d itio n s than would be w if?dh l i J aS c u r ? - e? u,pnient m anufacturing. The d u st le v e ls , n e v erth ele ss are iCM 05HA lim its . As long as th is i s tr u e , dust masks, p ro te c tiv e c lo th in g , c nge rooms, warning signs and sp e c ia l bag disposal are no t req u ired . Dust measurements ire re q u ire d , however, to dem onstrate t h a t th e l e ^ l s in a s p e c ific lo catio n are w ithin the OSHA stan d a rd s. - 2- AO8827 i In the manufacture o f fib e r glass rein fo rced p o ly e ste r o b je c ts , the edges anc some portion o f the surface are frequently sanded o r ground w ith a ro ta ry d isc grinder. This generates a cloud of v is ib le dust and i t is necessary to determine whether any free asbestos fib e r is oresent in the 'cloud. To check t h i s , samples were c o lle c te d a t four locations during the sanding or grinding of fin ish ed p o ly e ste r p a r ts . The r e s u lts , given in Table I I I , show no fre e asbestos fib e rs in any o f the operations. All of th ese data are based on M illipore f i l t e r counts by th e OSHA procedure. In addition to t h i s , la rg e r samples o f airb o rn e dust were c o lle c te d during Operation K and were stu d ied by sp ecial s ta in in g and m icroscopic techniques with various types of illum ination a t m agnifications up to 1000X. These, to o , fa ile d to reveal any free asbestos f ib e r . These data e sse n tially confirm th a t polyester re sin containing the usual le v e ls o f RG-244 w ill not y ie ld asbestos f ib e r counts exceeding the allowable values. * 5. Dust Control Although the data presented herein in d ic a te th a t RG-244, as i t is ty p ically handled in polyester tank manufacturing, gives dust levels w ithin the OSHA s ta n d a rd s , asbestos is an emotional s u b je c t; and the lowest p ra c tic a l levels are most desirable. ^ For small o p e ra tio n s, an a ir - or flu id -o p erate d a s p ir a to r w ith a fle x ib le pickup hose can be used to remove the th ix o tro p e from bags. This would preclude th e need fo r c u ttin g the end of the bag com pletely open, and would elim inate the subsequent dumping and bag-shaking o p e ra tio n . The d u st from the discharge o f an a ir-o p e ra te d a sp ira to r would, of c o u rse, re q u ire adequate collection. Empty bags can be disposed of by packaging them in p la s tic bags. Each bag o f RG-244 is over-slipped with a polyethylene bag which can be used fo r th is purpose. Larger p la s tic bags are commercially a v a ila b le i f th e RG-244 bags are not saved. Waste bags can subsequently be burned o r given to a re g u la r tra sh pickup serv ice . Dust which accumulates on ta n k s, f lo o r s , e tc . should be removed with a vacuum hose or washed down with w ater. Blowing w ith a i r can only re lo c a te the dust and may cause airborne concentrations to exceed the p re scrib ed lim its . Excessive dust can be created by poor work or housekeeping p ra c tic e s . Workers should be in s tru c te d to handle dusty m a te ria ls w ith care and to avoid undue c re a tio n o f dust by shaking bags, throwing them, e tc . R esp irato rs can be worn i f d e sire d and should be approved fo r the d u st encountered. Except fo r special circum stances, re sp ira to rs cannot be used to achieve compliance with OSHA re g u la tio n s . -3- A08828 TABLE I AIRBORNE ASBESTOS DST COUNTSH? DURING SUwor;G OF RG-244* P la n t A B C D E F G H Oata Reference -- 1929*46-2 1929-30-2 1929-5A-1 1929-50-3 1929-26-3 1929-24-2 1929-16-1 Bags Dunned 10 14 15 36 15 45 10 2S Dump Time (M in.) 10 9 21 12 8 20 24 15 Sample Time (M in.) 10 9 21 12 8 20 24 15 Special , V entilation(2) None None Hood o v e r th in tank opening None None None Hood o v e r mixing a re a None CEILING C o n c e n tra tio n F iber Count (F ibers/ce. >5^, ) 0 .7 1.2 0 .7 2 .4 0 .5 1.6 0 .8 2 .8 ^ A l l s a n p le s c o l l e c t e d 1n th e b r e a th in g ro n e o f th e o p e r a to r dumping th e RG-244. (2) ' 'S p e c ia l v e n tila tio n r e fe rs to d u s t c o lle c tio n eouipm ent a t o r n e a r th e dumoing a re a th a t is s p e c if ic a ll y in ten d ed fo r d u st c o n tro l d u rin g th e dumping o p e ra tio n . A ll p la n ts had varying measures o f o v erall b u ild in g v e n tila tio n . TLE II AIRBORNE ASBESTOS OUST COUNTS DURING EMPTY BAG RSfDVAL P lant A B B Data R eferen ce -- 1929-40-3 1929-40-5 D escription of O peration Sample taken 3 f e e t above w aste d isp o sal drum f o r erroty b a g s . (D uring dumping.) D ire c tly over empty bag sta c k in g a re a . Taken d u rin g dump. Empty bag s to r a g e a r e a . Taken d u r in g dump as bags were put in. S am ple Time (M in.) 10 23 24 F ib e r Count ( F i b e r s / c c . >5*.) 0 .4 0 .6 0 .4 A0862 ; TABLE II I AIRBORNE AS3EST0S DUST COUNTS0 ) HADE PORING SANDING OR GRINDING OF POLYESTER PARTS CONTAINING RG-PM Data Plant Raferance I 1929-40-4 (Furniture Molder) J 1929-42-7 (Boat Yard) . Description of Operation Sample Time (Min.) O perator sanding fin ish e d 23 polyester furniture parts containing~0.5% RG-244. O perator edge grinding on 12 h u ll containing**0.5% RG-244. (-20% fib e rg la s s ) Special V entilation^) Hood d ire c tly over grinding area. None (Outdoors) K -- K -- L -- ( Furniture Molder) O perator edge grinding on 13 p a rt c o n ta in in g -0.7% RG-244, 20% fib e rg la s s . Operator edge grinding on 4 p a rt containing 2% RG-244 Operator hand sanding 45 polyester parts containing **0.05% RG-244. General area sample. None (Closed room 8'x8' 8 '.) None (Closed room 3 *x81x8` ) None L -- (Furniture Molder) Large paver sander smoothing polyester parts containing -0.05% RG-244. 45 In te g ra l hood CEILING C oncentration F ib er Count ( F ib e rs/c c . > 5~) 0 0 0 0.2 <0.01 <0.01 ^Unless otherwise noted, all samples collected in the breathing zone of the operator during the sanding or grinding of parts containing "Calidna" RG-244. (2) Spec.ial vent.ilati.on refers to dust collection equipment at or near the dumping area that is specifically intended for dust control during the dumping operation. All plants had varying measures of overall building ventilation. A0883C