Document N2L3E8360RVwQgZmgjm6ZzYzQ

4400 Fifth Avenue Pittsburgh 15, la I PLAINTIFFS * . ^EXH -.I*BI*T*<*>* REPORT TO T-CTUA DIVISION ON . DUST COCTl-L II? IH5 ASBESTOS 7-JlTIUS PUCT H0GA1SVHLK, OaOr.OIA By ' w'.C.L. Heneon Engineering Director * April 7. 1950 Industrial Hygiene 1'ouncation of America, Inc. By: John ?. Ecilahon Ilenoging Director 1O it> U iNOuarmAi. hvoicnk ^ounoatton or amkmica. inc. REPORT TO `DUZTSD STATES ROHDES COUPAIJT TEXTILE DIVISION OH DOST CONTROL IN TBS asbotos tiotile punt HOOAHSVTIiE, GEORGIA MARCH 13 - 15, 1950 This visit was made primarily to adrlsa oa a dust control system for tha Ioobs la the asbestos wearing plant* Me ware also requested to adrlsa oa dust control la any of the other operations, all of which ware inspected. Particular. additional attention was d% evoted, therefore, to the preparation room and the carding machines* IP5TIHSSS nr HOGAHSmLS PLANT la 1947 Industrial Hygiene foundation conducted a preliminary surrey for the Asbestos Textile Institute, in the eoorse of which *dustlnees* levels la various dspartasnts of the several plants ware obtained* . In tha following table, dust levels characterizing the industry are listed, together with those in the several dspartaents of the Hogensvllle plant, tha lattsr figures being baaed on measurements smda by Hr* Guy during 1949 and early 1950* They show that the Kogansvills preparations dspartaent requires Improvement to bring It Into line with the best practices In the . i COi133 \ iNDUOTftlAl HVOIENC FOUNDATION OF AMCFICA. INC. Report to U.S. Robber Co., Tactile Dlrlslon, oa Duet Control la the Asbestos Textile Pleat, Bogansrllle, Oe. - Hereto 13-15, 1930. 2. industry. Duet lerele la the carding room ere somewhat higher than the majority of pleat*; reecawadatloae Tor improvement ere lacladed In this report* Duet concentration* et loose are greetor then In most other plants* Other departments ere comparable with those la the Industry generally. TABLE I catzPAEisan ar rcsnrcsa xh VARI005 FROCESSHIO DSTfJnXZUTS or TER ASBESTOS TSCT1LS XHDUSTCT T3BS05 THAT AT HOOAHSTZIXZ PLAKT Operation Crasher Wlllower Picicere Cards Flyer Twister Spinning Binding Loams Renee of Duet Concentrations W.p.c.r.r Typical of HogenerlUe Good Control in the Industry 5-10 5-10 5-8 2-1/2 - 5 2-4 S-5 2-4 5-10 lees then 7 Lees then 7 Less then 7 2-3 5-5 2-5 1-3 2-5 Fraction of Plants Baring Indicated Degree of Control 3/7 3/7 3/7 6/10 -- 5/9 5/7 2/B 4/8 M.F.C.F. Ulllloa particles per cubic foot. Ordinary twisting 4-7 million particles per cubic foot. INDUSTRIAL HYOISNC FOUNDATION OF AMCRICA. INC. Report to tJ.:\ Rubber Co,, Textile Division, on Dust Control la the Asbestos Textile I'lant, Bogansrlllm, Cs. - ICareh 15-15, 1950* a niATIKO DSRARttgKHT A study of dost sources st the looms ess facilitated by use of s strong light, and disclosed the principal sources to be at the harness, both shore end below the werp threads* Za addition, some dust originates st these threeds la front of the harness, between it and the ley beam, although materially less than at the former two locations* The major sources of dust can be controlled by installation of an sxhauat hood in the form of a narrow slot running the width of the loom, just behind the harness* It is estimated that control of dust shore the warp would be effected by an exhaust rate of 75 cubic feet of air per minute per foot of loom width* The same exhaust rata la contemplated through similar exhaust slot disposed below the warp threads in a position symmetrical (in relation to the plans of the wurp threeds) to that of the upper hood* It appears that there will be considerable difficulty in leading a 5-inoh duet into the space below the warp to communicate with the exhaust slot. This lad, 1a discussion with Hr* Ayer, to the suggestion that s nsin exhaust branch 6 Inches In diameter be brought to each loam with a HP*, the two brunches of which will be 5 Inches in diameter* One branch, for eventual communication with the hood below the warp, would be capped initially. The other branch would connect to the slot hood above the warp and exhaust the entire planned capacity of 150 offe per foot. This arrangement is attractive because if effective dust control could be attained with the upper exhaust hood alone, it would save the INOUSTKtAA. HYOIKNC FOUNDATION OF AMSFICA. INC. Report to U#3* Rubber Co., Taxtllo Division, oa Ttoat Control la th* Asbestos Tortile riant, Hogensvllle, Co. - Uaroh 15-13, 1930* 4 tailoring* that would bo roqulrod In extending the othor broaob to the opaeo below the werp* IT, on the other hand, experience with the' opper hood alone indicates e need Tor further improvement, the lower breaches sad their hoods would be constructed and tailored into position, without any changes in the mala exhaust iffteiu ' tteclrculatlon of Air free Past Collector Za connection with the problem of maintaining adequate humidity ^a and conserrlag heat la this dspertaent la tho winter, the question of recireulatlon free a dust collector was discussed. As a general rule, recirculation Is not considered e good practice where the duet In question le toxic# This is based on sons experiences where cloth filter collectors hawing basically high efficiency were not adequately maintained and leakage occurred, unnoticed by operating or maintenance personnel* This permitted discharge of duety air beck Into the vorixoom* Zn the present instance, however, we oonelade that recirculation from a high-effleleney cloth tube filter collector would be feasible and, in the eireuastances. Is reeomaeaded* This advice is based oa the following considerations: (1) A doth tube filter or stookine-leg type of dust collector le best suited to this areplication, end has adequately high ffloiancy* (2) The present situation is quite different froat thoea where serious recontaslastion has been noted due to poor collector maintenance* If a hypothetical duet exhaust system for the looms ware to die* * charge back into the room without say eleaning whatever, the dust 001202 INOUCmtAC HYOICNC FOUNDATION OF AMCMICA. INC. Report to tf*S* Rubber Co*, Textile Division, oa Dart Control la the Aebeetoe Textile Plant, Roc*navilie, Ga* - Kerch 13*13, 1950. 5, count* would be essentially of the sacs order of magnitude a* at present* It follows, therefore, that even though (due to sane gross oversight) major leakage developed in the dart collectors, the resalt in the cost extreme case would still re present e Material improvement over present conditions* (3) There is in existence ct present at this plant a oeiatenanee inspection system for the carding machine exhaust system in which da11/ inspection is sad* of all parts of It* This could be ex tended to include the new dost collector* Uoreover, the weekly dost counts now Bade routine1/ could be arranged to include one sample in the return air from the dust collector, thus providing an additional check. This would ensure good collector nsintenanee* Cloth Filter Characteristics The calleetlon efficiency of cloth filters is extremely high, so that efficiency percentages have little meaning* Thie factor need not, there fore, be of concern* ' A factor of major importance is In tho pressure drop characteristics and "elaanablilty'* of the filter doth* There are differences in this respect between different designs of such collectors, the details of which were dis cussed with Ur* Ayer, A given type of colleetor, at seme specific filtration Telocity, has a definite basic pressure drop Immediately after operation of the shaking aechaniasu 91th ordinary mineral dusts, this varies moat cooconly between 0*2 inches and 1*0 Inches per onit of filter velocity, in feet per Minute* It is important in proper design of an exhaust system, _and In GO i.2 - *> uu INDUSTRIAL. HYOICNK FOUNDATION OF AMERICA. INC. Report to U.S, Robber Co., Textile Division, on IXist Control in the Asbestos Textile Talent, Hogansvllle, Os. - Unroll 13-15, 1950. 6 particular, the selection of a fan, to know what this value is. There is no published date, nor can the collector nanofacturers provide It* In our discussions with Ur. Ayer, we outlined two ooursee of action whereby this lack could be filled. Two of the asbestos textile plants of tha writer's acquaintance have three dust filters in operation, handling asbestos dust from carding aaohlnee. These include the Aixaat, Pangborn, and ths Parsons, the latter a stocking-leg cloth filter. Ve are en--rnloatlng with these companies in an attempt to obtain pertinent pressure drop neesorenents. The other plan is related to the exhaust eystaa layout we prepared tentatively for ths HogansvlUe loom roan. It appears practical to install a system of overhead exhaust duets, thus avoiding the necessity for concern over the absenee of spaee below tho floor of tha loon roon. Our layout* consists In three separate systems of three different sizes. It appeared to Kr. Ayer and tha writer that the smallest of these could serve usefully as a pilot system, and a study of Its operating characteristics would enable resolu tion not only of the question of required dust collector size, but also that concerning the Importance of an exhaust hood below ths warp. On tha basis of an average loon width of 3 ft., there would be provided an exhaust rats for each loan of 450 to 500 cfa, which Beans exhaust capacity for the entire roon of 20,000 to 25,000 cfa. The dust collector size, (reforred to as though a single unit were being Installed), will be one having a cloth area probably not larger than 12,000 sq. ft., and possibly ss snail as 5,000 sq. ft. The difference In coet between these Units is . Drawn by Sr. Ayer's department and circulated with hia aanorandhn dated Barch 23, 1950, to be attached to this report. G0i2C-4 tNOUftTFIAi. MYQICNK FOUNOAVtON OF AMCMICA. INC. Report to tT*S. Rubber Co*, Textile Division, on teat Control 1a ths Aabaatoa Tart11# Plant, Hoganaville, Ca. - March 15-15, I960* 7* considerable, and a resolution of the also question therefore involves material sou* It will therefore pay to proceed on the basis of an experi mental unit* ' ,, Study of the effeetlTeaass of dust control la a partial installation cannot be aada vary effectively pj dust counts, beeause of dost still present in the ataosphere froa adjacent looas not equipped* It vlll, however, be poseible to draw acae conolnaiaaa by close observation of the dust sources with a strong light, as was demonstrated during our visit* le have no doubt that installation of tte type of exhaust system outlined will' reduce dust concentrations in the room to below five million particles per cubic foot of sir, end perhaps result in levels averaging three to four sillion* The obtaining of data far selection of the coat economical and affective else of dust collector, le, doth area, can be obtained on the initial installation by procedures outlined In the appendix to this report* CAKDIWO WICHIHE3 test in this department la pretty well suppressed, with exceptions acted below, by good enclosure of the main machine end its auxiliary equipment* The Braswell feed hoopers are totally enclosed, the enclosures pro vided with windows, with e 4-Inch branch exhaust connection* This la con sistent.-tilth common practice in the industry, hut the provision of s branch duct ea large as 4 inohes is of questionable necoaalty* This point la brought out here because the additional exhaust capacity required at other points noted below could be provided by reducing the flow from this unit* i - -001203 INDUSTRIAL. HYOICNK FOUNDATION OF AMKRICA. INC. Beport to U*S. Bubher Co*, Textile Division, on Dust Control la ths Asbestos Textile Plant, HogansvlUe, Go* - March 15-15, I960* 8* the apses between tbs weigh hopper and the sain cylinder Is well enclosed and exhausted by o 5-laoh branch connection* A good wooden enclosure is provided far the asin cylinder of the breaker cord end Its saxillary rolls* The enclosure is not exhausted. In stead, on auxiliary enclosure is attached at the coffer end and exhausted through 3-lneh branch* The finisher card, ilallarly enclosed, is exhausted at an auxiliary enclosure appended to the nsla cylinder enclosure above the feed roll; this enploys a 4-lnoh branch duct* A sinilsr enclosure above the Coffer roll is exhausted by a 2-inch branch duct* The sain cylinder In each card has a solid botton ixzperforate tray* The space under eaob card Is enclosed by and plates end the space exhausted through F-ineh branch-ducts* Dust Sources The following sources of dust wore noted with the aid of strong local iUatlnstlont (a) Sifting of fly to the floor below the coob on the finisher card Is apparent* A asjor aaount of fine tiust is apparent in the air directly above the cash* (b) Sons dust leaks outward from the apace under the breaker cards in spite of the exhaust provided by the 2-inch duct* (It Is not certain whether this sane source is significant on the finisher card*) (o) There is sene leakage of dost fron the exhausted box attached to the nain enclosure above the doffer roll on the finisher card* INOUSTMIAI. HVOIKN* FOUNOATION AMERICA. INC. Raport to U.C, Rubber Co.f Textile Division, oa Duct Control la the Aebeetoe Textile Pleat, Hogaasvllls, Ge. - March 13-15, 1950. 9 Recnrnmendatloaa la `the UrJit of theae observations, the following reeasaendatloas arc wade. It la believod thoy will reduce duet concentrations la the card roon to two to three alllion, and thus sake this department eoaperable with beet practice la the Industry* (1) Provide an exhauet slot above the eonb on the finisher card* If this slot eaa be positioned fairly close to the coab, It should be possible to afreet good dust control with air flow of about 300 cffe per eonb* This would require a branch duet not leas than 4 inches IndLeaetar* (2) Isprovs the enclosure under the breaker card, if possible, by extending the end plate upward another foot or so, to reduce the area of the opening. Observe the results oa one aachine by strong illasination. If dust still escapes, the 2-lnch duct should bo changed to a 3-lneh duet. (3) Increase tbs disaster of the dust attached to the duffer roll enclosure oa the finisher card from 2 Inches to 2$ Inches* (4) The Increase la exhaust oepeelty outlined In the above paragraphs eaa be provided, if necessary, by reducing the 4-iaoh pipe oa the feed hopper to 3 laches, and the 5-iact duct oa the enclosure betweea the weigh hopper feed roll on the breaker card to 4 inches. These changes, however, nay not be required. t!0i2 U i <NourmAu hvoicnc pounoation op amkpica. inc. Report to U,S. Rubber Co** Textile Division, ou Hurt Control la the Asbestos Textile Riant, HoeansrlUe, Ce. - torch 1S-15, 19S0. 10 raSTARATIOK ROCK Oast Incident to Tiber blending on the bedding floor *ee the subject of ease study, Vo discussed with Mr* Ayer the feasibility of an enclosure consisting In eortaln sells that extend froa the celling above the bed and leave en open eree et the front, adjacent to the machines, elx feet high and the full eight-foot width* bnt on the other three sldea, restricting the opening to about two feet high* The resulting open area would total aboat 100 sq* ft*, and good dost control would result with an exhaust rote of only 7,000 to 8,000 cfsu Ur* Ayer will take this under advisement* One of the two dry pen eruahera le enclosed and exhausted. The other la In ewwsn one, and should be similarly equipped, Cording Machine Ixhauat Ratos It is of Interest to compare the basic design of the carding machine exhaust in different plants with those In use in various other plants. This le beet described by reference to the total rate of exhaust fro* carding machines, togsthsr with the average dust count, ee shorn In the following table IMOUSTftUU. HYOIBNf FOUNDATION OF AMKFiCA. INC. Report to 0*5* Robber Co,, Textile Division, on Dust Control la the Asbestos Textile Pleat, Rogsasrllle, Go* March 15-13, 1930. 11* TABLE 11 CAKES Pleat Exhaust Bate eih/2 Cards A . 1300 B 2200 S 3800 a 9400 B 2000 Hogaasvllls 800 *H.r.C*T. Killian pertlclee per oubio foot of sir. M 1 (1 Average Dost Count M.P.C.T.* 2-3 1-2 l - 3 2-3 2 - 5 Zt Is noteworthy that the HogaasriUe Installation should be naked aaoag the aost efficient, Inasmuch as it effects pretty good dust ooatrol with e loser exhaust rote than say of the other pleats* 0-T12QD INOUTM(Al_ HVOIKNC POUNOATM3N OF AMCRICAi INC. Report to C*S. Rubber Co*, Textile Division, on Duet Control in the Asbestos Textile l'lent, Hogonsrille, Ca. - March 13-15, 1950. 12 Oanercl Current preetieee at the HogansviUe Plant ere particularly neri- torioue in two respects* One of theee is in the weekly dust count made by Kr. Coy, Other pleata hare good duet control records, but none are obtained by company personnel, sad they are therefore less complete. The other noteworthy practice is the daily inspection of the carding rocs exhaast ayeteou This is also done in oas or two of the other plants* It was recoBwended to Xr. Ayer la this oeaasetioa that the looal illumination technique demonstrated by the writer be added to the duet count Inspection routine, and the resulting observations be incorporated in the weekly report* ffe dlsoussed with Mr* Ayer the inadequacy of preeeut dust count nethods in general vogue, where dust concentrations hate been brought to the preeent levels, and of the poselbllity of a cooperative Investigation supported by a few of the leading aebeatoe textile companies, aimed at a more certain evaluation of the eebestoele besard in proseat conditions* 0Q1210 INOU*TAUU_ HV4ICNC FOUNDATION OF AMCNICA. INC- Report to U*f. Robber Co., Textile Division, ob Duet Control la the Asbestos Textile Pleat, Kogeaerllle, Ge. - Iferoh 13-15, 1990* 13 APfZWDlI TSST raOCSSPRE Off A PILOT DOST CaLLBSTQR FOR 3TABLI3HHi3T OF PRESSORS-LOSS CBmCTiBISTSCg The following etepe ere talon, la the order Indicated: (1) At ead of ea operating cycle, Just before shaking bags, measure: (a) Static preseore bp U-tabe maaometer oa the clean-air aide of collector, la chamber housing, not la outlet duct. (b) Static preseore oa daetjr-elr side of collector* (e) Air floe through collector by lltot tube (Q^)* Comment: (a} - (b) gives pressure drop loaded with duet* Air floe through collector, Qq, ie proportional to square of inlet static pressure* This relation may be used to calculate later air floe bp measurement of inlet static preeaore alone* (2) Shat down faa ead operate mechsnlsu Remora duet from hopper (which should be empty before shaking} ead weigh whan convenient, (height = V lbs*) (3) 3tart faa again and measure saae quantities (e) (b) (c) listed under (1} C ceaseat: (e) - (b) at this stage gives pressure drop with "clean* filter R coiai: INOUTKfAl MYOICNC rOUNOATtOK OF AMKAtCA. INC. Report to U.S* Rubber Co., Textile D1rialon, on Dust Control in the Aabestoe Textile Plant, Eogemarllle, Qa. March 13-15, 1950. 14 Air flow through collector * % Cloth am, eq. ft. A and nitration veLocity, YQ s %/A Than - y -- JL laohoa d rop/, at 1 fp filtration velocity. wo Slaoa preaaure drop, R, through, the cloth at atart of operating oyole, varlea directly with To. thin figure enablea calculation of Initial praseure drop for any else of collector. \ The tncreaae la preaaure drop (R^ Inches] due to the temporary layer of doat on the cloth la RdI where, w la ooncea of dust per aqaare foot of cloth T la %/A The total preaaure drop at end of the cycle la, then Ra%*% Ihe Talus, *0. has been found frae data under (1) T la Qjyto, the filtration velocity given by the data obtained under (3] w la obtained from the weight of duet, and la in ounces per square foot of cloth R waa found under (1), aa (a) - (b) Substitution In equation gives % :o J. A. tNOUSTAIAU HVOICNC FOUNDATION OF AMMICA. INC. Report to U.n. Rubber Co., Text11 TJlrisloa, on Dust Control in the Asbestos Textile I'lant, BogansrlUs, 0a* - torch 13-1S, 1950* 15 hxaepla of application! Assam ^ la found to bo 0*5 inches par 1 fpn and la found to bo 0*2 lacbea por 1 fpn per 1 os* per eq. ft. Abet sill bo pressure drop after a collector baa aeounolated l os. per square foot (equivalent to Z bra* operation)* Air flow at end of oyele la 20,000 cfai and elotb area la 10,000 eq. ft* Eolations Q/A 20.000 10,000 2 fpa . R a 0.5 (2) 0*2 (2) US * 1*6 Inches