Document rDD9Y3ao4L6od3Xw8Ozn6LMa

FILE NAME: Shipbuilders Council of America (SHIP) DATE: 1971 Feb 18 DOC#: SHIP011 DOCUMENT DESCRIPTION: Memo to Accident Prevention Committee with Draft Manual on Handling of Insulation Materials SHIPBUILDERS COUNCIL OF AMERICA 1 7 3 0 K STREET N. W. WASHINGTON, O.C. aOOOB 2 0 2 (3 3 5 - 7 7 2 2 F eb ru a ry 18, 1971 TO: ACCIDENT PREVENTION COMMITTEE SUBJECT: D raft M anual on Handling of Insulation M aterials E nclosed is self-explanatory correspondence from Duncan A. H oliday, R esea rch A sso cia te P r o fe sso r at M t. Sinai School of M edicine on the above su b ject. W ould a p p recia te your forw ard in g co m m en ts d ir e c tly to: H arry Howard A ssista n t to the V ice Pres-bdent B ethlehem Steel C orporation 25 Broadway New York, New York 10004 M r. Howard is a m em ber of the Shipyard M anual C om m ittee rep resen tin g the Sh ipbuilders C ouncil of A m erica . I would a lso app reciate your m aking a copy available to Shipbuilders C ouncil. cc: Edwin H artzm an J. M. C onley, Jr. Thom as J. Defoe John A. Byington W. B . P o w e ll E . P . Ruddy S e c re ta r y ^ M I I B I T ------ - -x: - - _ _ V . SBCA 6030 I S3 MO U N T SINAI S CHOOL OF MEDI CI NE o/ The City University of New York F I F T H A V E N U E A ND IOOTH S T R E E T - N E W YORK, N.Y. 10013 DfpaNmfnl of Community 3Wfd(cint Februa ry .9, Tor From: Subject: Members o f Shipyard Manual Committee Duncan A. Holaday ^ Rough D r a f t of Manual f o r S h ip y a r d s Mr. R e i t z e and 1 have composed a rough d r a f t of a manual o f recommended p r a c t i c e s f o r handling i n s u l a t i o n m a t e r i a l s in sh ip b u ild in g , ship re p a ir and shipbreaking. This is enclosed f o r your e d i f i c a t i o n , comments and s u g g e s t io n s . T h is d r a f t was prepared with the e x p e c t a tio n t h a t the committee members ' i * vj * f^ o o i i a 1 o iuii i iu O A fJa i tu , a- u*vit UiC. tI V* AI. t- y ly> I I W w r i t e the m a t e r i a l . T h e r e f o r e , t h i s document i s not intended to be complete -- but sim ply a t a r g e t . We plan on using p i c t u r e s and design sketch es of control procedures or equipment where a p p r o p r i a t e . Some o f these items we have obta in ed from Mr. Man gold and Mr. Ay, but would a p p r e c i a t e any m a t e r i a l which you may have and s u gg e stio ns <?n what would be d e s i r a b l e to in c lu d e. P a r t i c u l a r l y needed (in our opinion) a r e d is c u s s io n s of general d i l u t i o n v e n t i l a t i o n and s u b s t i t u t e m a t e r i a l s . Each o f you should have sug g e stio n s on th ese or o t h e r t o p i c s , and' you ar e urged to c o n t r i b u t e . We would a p p r e c i a t e your comments by March 1, 1971. A f t e r these a r e r e c e i v e d , we w i l l r e w r it e the" manual, snd you a copy and arran g e a meeting a t which we hope to a r r i v e a t a f i n a l form. v DAH:lkh Enel. (i-xx. *it K.r K fa et d . ctJeajZ^K, -t' z L i ' Si ncerely, Cv Duncan A. Holaday y Research Associate Professor Recommended P r a c t i c e s f o r Handling I n s u l a t i o n M a t e r i a l s in S h i p b u i l d i n g , Ship R e p a ir a!nd Shipbreaking Introduction A. B i o l o g i c a l e f f e c t s o f a s b e s t o s ( s u c c i n c t summary) B. Tradesmen who a r e exposed to i n s u l a t i o n dusts (1) I n s u l a t i o n workmen 4 (2) Pipe f i l l e r s , steam fitters (3) Other trades working in area s where in s u l a t i o n i s being a p p l i e d or removed ' - C. O peratio ns which g enerate l a r g e amounts o f dust (1) Removal o f i n s u l a t i o n ( r i p - o u t ) . (2) Mixing mortar (3) Cutting insulation m aterials * (a) On s i te .. . ........... (b) Fab shop ` .. ' ; (^) Clean-up and waste handling ' ' ' (5) Blocking o r hammering on blo ck or pipe cove ring - *. to seat material ' (6) Warehousing or storage 2 Control of A s b e s t o s - c o n t a i n i n g dusts by use of s u b s t i t u t e materials * * ! A. F ib e rg .ia s s f o r b la n k e t and pad f i l l i n g B. Pipe co ve ring and b lo ck with reduced a s b e s to s co nt ent C. Use o f m a t e r i a l s t r e a t e d with dust s u p p re ss an t Reduction o f dust by changes in work methods , A. Minimizing hand c u t t in g a t the job s i t e s and use of down-draft, exhaust-ventila ted tables B. Premixing a s b e s t o s m o rta r*d o c k s id e ' C. Prom? r i n g a s b c c t c c m orta r i r. p 1 LI v, bay b. D. Wetting a s b e s t o s cloth, and f i l l e r s before pad and blanket fabrication > * l E. The use of drop c l o t h s at jo b ' s i t e s F. C o l le c t i o n and containment of wastes as they are produced G. Clean-up a t end o f jo b o r end o f s h i f t , using vacuum cleaners - ' ' H. Conducting a l l p o s s i b l e i n s u l a t i o n work in the shop ' r a t h e r than on shipboard ' I . Packag i ng of f a b r i c a t e d p a r t s f o r t r a n s p o r t from shop to ship | Reduction o f dusts by use of lo c a l exhaust v e n t i l a t i o n A. V e n t i l a t i o n of la r g e power t o o l s * (1) Band saws (2) Gang saws B. V e n t i l a t i o n o f hand power t o o l s ' ' C. Use o f hoods and down-draft t a b l e s f o r pad and blanket fabrication Reduction o f d usts by general d i l u t i o n v e n t i l a t i o n Control of numbers exposed '' A. Scheduling i n s u l a t i o n work to minimize numbers o f other tradesmen in the area B. ' i s o l a t i n g a r e a s in which i n s u l a t i o n i s being removed C. Use o f u n t r a i n e d men in c lu d in g s h i p ' s company, f o r r i p - o u t should be held to a minimum. Personal P ro te ctiv e Equipment ' . * A. R e s p ir a to rs -- give circum stances in which each type should be used .. ' (1) P a r t i c u l a t e .fi 1t e r in g (a) Reusable (b) Disposable . , ' . 4 \ r ' t .i I VII A (continued) * . (2) A i r-supplIed I * ( a ) A i r- 1I ne (b) Self-powered ' ' B. P r o t e c t i v e c l o t h i n g V III. Education of workers Constant t r a i n i n g and updating of information IX. . Medical supervision , * ' ` \ X. Summary A . - Measures involving l i t t l e c o s t which can immediately ' be adopted B. Those measures in v o lv in g more c o s t l y engineering and cap i t a 1 funds. ' . . . ROUGH DRAFT 2/8/71 1n t ro d u c tio n ' ......... ' ` > Inh alation of asbestos f ib e r s has caused serious in ju ry to workmen. Many s t u d i e s have found t h a t c a s e s of a s b e s t o s i s , lung cancer and p le u r a l and p e rito n e a l mesothelioma occur fo llo w in g exposure to a i r b o r n e a s b e s t o s . To prevent these serious e f f e c t s , i t is necessary to reduce exposure to asbestos dust to the lowest f e a s ib le le v e l. Exposures to high concentra t i o n s , even those o f o n l y a few minut es' d u r a t io n , should be avoided. ` Handling insulating m aterials during ship construction, s hip r e p a i r and sh ip b re ak in g o p e r a t i o n s can expose many people he s i d e s th c c c d e s cr ib e d ec ir.ee la Lion w o ik e i s . P i p e f i t t e r s arid s t e a m f i t t e r s may have to remove i n s u l a t i o n during t h e i r work and r i p - o u t o f old i n s u l a t i o n may be done by any group. F r e q u e n t l y , members o f o t h e r c o n s t r u c t i o n tr ad es a r e working in the same a r e a s where i n s u l a t i o n i s being a p p lie d or removed and are thus a ls o p o t e n t i a l l y exposed to airborne asbestos dus't. Although areas . /> if resp o n sib ilities w ill - --------- - - - d iffe r from,yard to yard, one resp o n sib le person, perhaps the in d u s tr ia l hy g i e n i s t or the s a f e t y o f f i c e r , should meet with the job ' s u p e r in t e n d e n t and the j o b foreman to survey the job before any work i s s t a r t e d . The o b j e c t of t h i s survey would be to. 2 determine what and where the p o t e n t i a l dust problems w i l l be. T h is committee would then recommend procedures to reduce the asbestos dust exposures during the completion of the job. The committee report would be a v a i l a b l e to the c o s t estim ators as well as those concerned fo r the day-to-day work s c h e d u le .. O peratio ns which gen erat e la r g e amounts of dust in c lu d e : 1. R ip - o u t o f o ld I n s u l a t i o n ' 2. Mixing asbestos mortar 3. C utt in g i n s u l a t i o n m a t e r ia l e i t h e r on s i t e o r in t - . fa b ric a tio n shops k . Blocking o r hammering on b lo ck or pipe covering to 1 seat m aterial. 5. Warehousing and storage of m aterial' 6. Clean-up and waste handling. P a r t i c u l a r e f f o r t s should be made to co nt rol dust dispersion during these operations to reduce peak exposures and prevent general contamination of the atmosphere of the j work a r e a . '3 ' . The f o llo w in g s e c t i o n s o f t h i s manual d i s c u s s in d e t a i l procedures which have been used ;to reduce atmospheric contamination by a s b e s to s dust. These procedures have been assembled from s e v e r a l sources with major c o n t r i b u t i o n s made by the programs developed a t the Puget Sound and Long Beach Naval S hipyards. ` ` I . Control of A sb e s t o s - C o n t a in ln q Dusts by Use of S u b s t i t u t e Ma t e r ?a 1s . Substitution of m aterials containing, less asbestos f i b e r or no f i b e r a t a l l , i s becoming more common in ship construction. Before a material is substituted for asbestos, c e r t a i n p o in t s must be c a r e f u l l y co n s id e r e d . From a h e a lth * ' .point of view, one must guard a g a in s t that which has happened Ip other environmental s i t u a t i o n s -- where in the h a s t e to r i d s o c i e t y o f a known p o l l u t a n t , a substance whose p o t e n t i a l hazards a r e unknown has been s u b s t i t u t e d . , A second c o n s i d e r a t i o n must be; w i l l the new m a t e r ia l meet engineering s p e c i f i c a t i o n s and w i l l i t perform adequately under conditions of use. " M a t e r i a l s c o n t a in in g reduced amounts of a s b e s t o s have been used in the following a p p l i c a t i o n s : 4 , ' r A . F i b e r g l a s s f o r b la n k e t and pad, f i l l i n g Amosite blanket covered with asbestos cloth is a , standard m a te ria l fo r making v a lv e and flange pads. Sub s t i t u t i o n o f the proper grade o f f i b e r g l a s s as a pad f i l l e r not only reduces asbestos dust during fabrication and i n s t a l l a t i o n but a l s o tends to le sse n the problems during subsequent " r ip - o u t ' * .' Asbestos c lo t h which has i p u. iv.u i1 1iU* ut 14c. u* 11ut *i cr d use should a l s o be encouraged. B. Pipe c o v e rin g and b lo ck w ith reduced a s b e s t o s content Over the years the manufacturers of calcium s i l i c a t e m a t e r i a l s have been s t e a d i 1y 1reducIng the percentage of asbestos fib e r in th e ir m aterial. Serious consideration should be given to those products co n t a in in g lower amounts of asbestos fiber. Several B r i t i s h firms have introduced j ; a s b e s t o s - f r e e c a lc iu m s i l i c a t e b lo ck and pipe c o v e r in g . To date, however, t h i s m a t e r i a l has not been adequately e v a l u ated in the UnT'ted S t a t e s to determine how i t w i l l perform in use. 5 1 1 1 . ' Reduction of Dust by Changes in Work Methods , ' In many o p e r a t i o n s , changes in work p r a c t i c e s w i l l I ' reduce dust disp.ersion very s ig n if ic a n t ly . A ll of the pro cedures d is c u s s e d in t h i s s e c t i o n have been u t i l i z e d and found to be e f f e c t i v e . A. Mixing Asbestos Mortar T h i s o p e r a tio n h a s " u s u a l l y been done a t the jo b s i t e . While the time spent in mix'ing i s q u i t e s h o r t , c o n s id e r a b le dust i s produced. A t e s t e d method o f co n tro l is to mix the mortar dockside, package the mixed mortar in several con ta in e rs for tran sp ortatio n to the job s i t e . Mortar is a v a i l able packaged in sev eral s i z e s of p l a s t i c bags which have a spout through which water Is introduced. % l S u fficie n t water is added to moisten the morta r; a f t e r premixing, the bag i s opened and the remaining water added. The carto n in which bag is packaged serves as a mixing box and waste co n tain er. E it h e r oi th e se methods e l i m i n a t e s dust d i s p e r s i o n a t the jo b s i t e . . P r e - c u t t i n g pipe co veri ng and b lo ck in the f a b r i c a t i o n shot Hand-cutting o f p ip e coveri ng and block should be kept t< an a b s o l u t e minimum. Bend s e c t i o n s , pipe cover lengths and b lo cks should be cu t in the f a b r i c a t i o n shop on e x h a u s t - v e n t l l a 1 6 J. equipment. ' t sl The cut s e c t i o n s a r e d ip p e d `in water, packed in p l a s t i c bags which are then labeled. T h is procedure* insures - ` I t h a t the cut s e c t i o n s a r e s t i l l damp and r e l a t i v e l y d u s t - f r e e when they a r e a p p l i e d . ' . \ *- C. P r e - s c o r i n g b l o c k s. I n s u l a t i o n b lo cks should not be scored a t the jo b s i t e . Blocks which have been p re - s c o re d by the manu f a c t u r e r can be purchased, or standard b lo c k s can be scored in the f a b r i c a t i o n shop using an e x h a u s t - v e n t i l a t e d gang saw. ~u i . im m a iitH j . - . l 1 . - - _ ' a b o cu lu I I cis i l l Ciic bu VM Some pipe a s s e m b lie s a r e q u i t e i n t r i c a t e and a r e t r o u b l e some to lag w h i l e in p l a c e . A s a t i s f a c t o r y method o f doing th e se j o b s , p a r t i c u l a r l y during s hip r e p a i r , i s to remove the assembly in c o n v e n i e n t l y s i z e d s e c t i o n s , t r a n s p o r t them to the shop. Here the o ld i n s u l a t i o n i s removed, any n e c e s s a r y r e p a i r performed and the completed s e c t i o n re- la g g e d . Not o nly i s dust d i s p e r s i o n reduced, but i t i s much more convenient to r e - l a c the s e c t i o n in the shop than when i t I s in p la c e shipboard. 7 / * - E. Hand-cutting at job s i t e s . j Some ha n d -c u ttin g a t jo b s i t e s i s unavoidable. Dust d i s p e r s i o n can be reduced to a minimum by doing a l l sawing on a downdraft t a b l e . T h e d e s i g n o f such a ta b le i s shown in F i g . ____ . A small i n d u s t r i a l vacuum c l e a n e r s e r v e s as an a ir - m o v e r . A p l a s t i c bag under the t a b l e c o n t a in s the l a r g e r dusts and wastes. ' . p F a b r ic a t io n of'p ad s and blankets . Where p o s s i b l e , pad f i l l i n g and a s b e s t o s c l o t h should - be done in l a t e r a l l y v e n t i l a t e d hoods. In a l l cas es both the f i l l e r and the a s b e s t o s c l o t h should be dampened before u s e . See F i g s . ______ ______ % 2. Housekeeping and Clean-up . . Area and atmospheri c contamination with a s b e s t o s d.ust can be reduced g r e a t l y by m e tic u lo u s a t t e n t i o n to the co ntro l o f dust and l a r g e r w a ste s. Drop c l o t h s should be p laced on the deck'under each working area to prevent spread of wastes. 9 Scrap should be dropped into p l a s t i c bags as i t i s produced s 8 r a t h e r than on the deck to be picked u p - l a t e r . Work ar eas should be vacuumed a t the lunch break and end of the- s h i f t . I In a l l . p o s s i b l e ' i ns t ance s , the workmen should be r e s p o n s i b l e f o r c l e a n i n g t h e i r own a r e a s . Where work r u l e s p r o h i b i t t h i s , the cl e an - up men should be under the s u p e r v i s i o n and control of the i n s u l a t i o n foreman to I ns ur e proper a t t e n t i o n to t h i s very Important' matt er. . , IV. Reduction of Dusts by Use of Local Exhaust V e n t i l a t i o n _ A. V e n t i l a t i o n of l a r g e power t o o l s . - Band Saws * The e x t e n s i v e use of band saws both in dockside f a b r i c a t i o n shops and on l a r g e r s h i p s ( a i r c r a f t c a r r i e r s ) ` i * * in the v e s s e l i t s e l f , make emi s s i ons from band saws a major source of a s b e s t o s dust. Control d e v i c e s f or such saws have been known f or years and a r e r e l a t i v e l y simpl e d e v i c e s . Conventional low v e l o c i t y , high volume systems using a ne gat i ve p r e s s u r e bag house a r e u s u a l l y more p r a c t i c a l in a fi xe d i n s t a l l a t i o n f a b r i c a t i o n shop. !V A (cont in ued) Because some degree o f p o r t a b i l i t y i s d e s i r a b l e In a temporary shipboard fa b ric a tio n area, a high v e lo c it y , low volume u n i t i s. des i rabl e. ( F i g . __________ ) * S T h i s type o f u n i t can a l s o be designed to contro l dust e m is sio n s from t a b l e saws and gang saws. Because of i t s p o r t a b i l i t y , high v e l o c i t y u n i t s can a l s o be used to perform v a r i o u s housekeeping t a s k s on jo b s i t e s . O > * <*. _ r VCllLI IdLlUH u _ ,, ,,r 1 nu High v e l o c i t y , low volume c o l l e c t i o n systems adequately handle most small power t o o l s . Saber saws f o r c u t t i n g pip e \ coverif.g and, r o t a r y saws f o r c u t t i n g a s b e s to s cement board a r e well c o n t r o l l e d with th ese systems. ( F i g . __________) V. / 10 Control of Number o f Workmen Exposed ' A . Scheduling o f i n s u l a t i o n work - -- ' 1 ......... --......................., - i Standard in d u strial hygiene practices ca ll for isolating operations which contaminate the atmosphere with toxic m a t e r ia l* Area's where i n s u l a t i o n work i s being done should be i s o l a t e d by p l a s t i c c u r t a i n s or o t h e r means. Whenever p o s s i b l e , work shoulc be scheduled to minimize the numbers of o th er tradesmen in the a r e a . Ship c o n s t r u c t i o n o p e r a t i o n s a r e more r e a d i l y scheduled ^than a r e shi p r e a p i r or s h ip - b r e a k in g j o b s . However, every I 11 \ e f f o r t should be made to keep the number o f men exposed a t a minimum. In p a r t i c u l a r , rip-out of old in su la tio n should t , always be i s o l a t e d and i f n e c e s s a r y performed on an o f f - s h i f t . T rain e d workmen s u p p l ie d with proper p r o t e c t i v e equipment should always be used f o r r i p - o u t work. -Rersonal P r o t e c t i v e Equipment In a d d itio n to -d ust-su p p re ssio n and dust control pro cedures, personal p r o t e c t iv e equipment is often necessary to reduce exposure and l i m i t the spread of contamination. The equipment described below Is used in control programs. A. Protective .clothing . P ro te c tiv e clothing is required to prevent carrying a s b e s to s oust into l o c k e r rooms thus exposing o th er workmen and e v e n t u a l l y i nto i n s u l a t i o n workers* homes. A s a t i s f a c t o r y type of p r o t e c t iv e clo th in g c o n s i s t s of re sin impreg nated paper c o v e ra lls. These are inexpensive, readily d is posable, and e lim in a te laundering . and p i l f e r a g e problems. They a r e worn .for one s h i f t , then removed and "'placed in p l a s t i c bags for disposal with o th er a s b esto s-c o n taining wastes. These coveralls provide su ffic ie n t protection for a l l but extreme co nd itio ns. ' . \ 12 / B. R e s p i r a t o r y p r o t e c t i v e equipment ~ Even i f dust suppressio n and dust control procedures a r e used, some o p e r a t i o n s g enerate so much dust th a t i t is impractical to maintain atmospheric-concentrations of asbestos f i b e r s below the Threshold L i m i t Value (TLV), and r e s p i r a t o r y p r o t e c t i o n must be provided to the workers. A v a r i e t y of r e s p i r a t o r y p r o t e c t i v e equipment i s a v a i l a b l e from which d evic es s u i t a b l e f o r v a r i o u s s i t u a t i o n s can be s e l e c t e d . American Nation Standard Z88.3-1971, Safety Guide for Respiratory Protection A g a i n s t Asbes tos-Con ta in ing DustsJ should be r e f e r r e d ' t o f o r de- : i ^~Ma :i l~l 1O--i -l H--U- Ui % . "N. '1 * A i r - s u p p l i e d r e s p i r a t o r s , -Extremely dusty jo b s, such as rip-out of old in su la t i o n where dust c o n c e n t r a t i o n s exceed 10 times the TLV, r e q u ir e use of a ir - s u p p lie d re sp ira to rs which w ill d e liv e r clean, d u s t - f r e e a i r to a f a c e p i e c e o r hood. Two general types ar e a v a i l a b l e ; a i r - l i n e and self-powered. (a) A i r l i n e r e s p ira t o rs in which a i r is supplied j to a hood give the g reatest degree of protection. A i r i s fed to the hood from a compressed a i r l i n e . The a i r source must be lo cated in an uncontaminated area and the a i r must be f i l t e r e d to remove o i l and water 13 m i s t s before d e l i v e r y . P l a s t i c , d is p o s a b l e hoods are a v a i l a b l e commercia11y. P r e f e r a b ly the a i r l i n e should * be fas tened to the hood with a ^ u ic k - d is c o n n e c t f i t t i n g , (b) Self-powered a i r - l i n e r e s p ir a t o r s A i r - l i n e r e s p ir a to r s connected to a compressed a i r supply impose l i m i t a t i o n s on movement, and t h i s l i m i t a t i o n can be troublesome. Self-powered r e s p i r a t o r s do not impose such l i m i t a t i o n s , but do add to the equip ment which the workman must c a r r y and r e q u ir e c a r e f u l ' . jAL maintenance. B a t t e r i e s must be recharged a-^trei2r-eao-h--u-&e, f i l t e r s replaced and o t h e r maintenance done r o u t i n e l y . Workers u s u a lly a tors . prefer these devices f to a i r - l i n e respir' 2. Pa rt i cu 1a te- f i l t e r i n g r e s p i r a t o r s . ' There a r e s e v e r a l types of p a r t i c u 1a t e - f i 1t e r in g re s p ira to rs . Those equipped with a half-mask facepiece are co n s id e r e d most s u i t a b l e f o r use by i n s u l a t o r s . Only those approved f o r p r o t e c t i o n a g a i n s t a s b e s t o s c._st by the government -agency r e s p o n s i b l e f o r testin g r e s p i r a t o r s sh o u l d be used. Thes d e v ic e s a r e recommended f o r p r o t e c t i o n in those s i t u a t i o n s where the atmospheric c o n ce n tra tio n o f a sb esto s f i b e r s does not exceed 10 times the TLV. A l l the recommendations f o r r e s p i r a t o r f i t t i n g , t r a i n i n g o f workmen and maintenance, d e t a i l e d in Z88,3-1971 snould be follo wed. . . > ' ' (a) Reusable p articulate filte rin g respirators A variety of reusable particulate filte rin g respira t o r s are a v a i l a b l e . Tc Insure proper f i t t i n g , several d i f f e r e n t makes should be a v a i l a b l e from which the worker can s e l e c t one. No one model r e s p i r a t o r f a c e p i e c e w i l l f i t a ll fa ce s. Routine maintenance is absolutely necessa to repla ce clogged f i l t e r s and leaking in h a la t io n or ex halation valves, . I Un-maintained r e s p i r a t o r s can be booby t raps. - (b) Disposable p a r t i c u l a t e f i l t e r i n g r e s p ir a to r s Operation o f an adequate r e s p i r a t o r maintenance program can be troublesome and, i f o nly a few men a r e involved, impractical. Disposable respirators are J avai lable which a r e designed to be worn f or no longer than one s h i f t and then discard ed. .* * Inherently, these d e v ic e s a r e not as r ugged as a r esuab le r e s p i r a t o r and " no a t t e m p t should be made to use them longer than one 15 ` t i i Education and T ra in in g * No dust co n t ro l program can be e f f e c t i v e u n l e s s work men and s u p e r v i s o r s understand the hazards a s s o c i a t e d with the f jo b s , the sources of the hazards and the reasons fo r following recommended procedures c a r e f u l l y . -Understanding i s o n ly ob ta in e d by education of personnel and t r a i n i n g in c o r r e c t operating procedures. For an education and t r a in i n g program to be s u c c e s s f u l , both management and la b o r must be concerned and p a r t i c i p a t e . As with a l l s a f e t y programs, i t i s e s s e n t i a l t h a t f i r s t - l i n e s u p e r v i s o r s be i n t e r e s t e d in. and co o perate in the work. . The harmful e f f e c t s * tro llin g asbestos dust are . of neglect of procedures for not apparent f o r many y e a r s . \ con There f o r e , i t i s more d i f f i c u l t to co n vin ce workmen of the n e c e s s i t y of following ru le s for working with in s u la tin g m a te r ia ls ,than i f p h y s ic a l hazards were involved. However, those shipyards which conduct educa ti on and t r a i n i n g programs report good success. I . J Education in hazards associated with use of insulating . m a t e r i a l s and i n s t r u c t i o n in c o r r e c t work p r a c t i c e s should be ' x 16 included in a p p re n tice t r a in in g programs. For the time being, however, t r a i n i n g and education must be done a t the s h i p y a r d s . * . T h i s must be a co n tin u in g program and should in clu d e not o nly i n s u l a t i o n wor kers, but o t h e r s who may o c c a s i o n a l l y Work with . ' . I . insulation materials.