Document oD1X8oOmnLmJgpM8wKNg7gyn7

*- ( s# * THE DOW CHEMICAL COMPANY TCUl (t I V I 11 O nittrotn Tf*A* rtni October 25, 1968 John Mayfield . Solvents Laboratory A-2422 'pW;CON'IDENTIAL cc: J. A. Skaggs R. o. Brown D. J. Kilian, M. D. HOOD VELOCITY INSPECTIONS AND ANALYSIS OF AIR SAMPLES IN A-2410 LAB I, llood Velocity: Face velocity of four fume hoods was checked during the last week of September, 1968, The minimum velocity ordinarily rreommcniled to Jnmtre ndripmi c prut eel ion in 100 1pm. All hooda were marked at (lie sanli level Whleh. gave a reading uf 100 fpm. Three of the four ; hoods were not conn 1 tiered twprovidevpdequatc air flow, and, under norma] use, would probably not afford protection against entry of fumes into the room. In addition to the four fume hoods, a hooded structure is being used above a sink to colled fumes from chemicals dumped iiiLn the sink or fn:o laboratory procedures being eoieliiel e.1 tin i hr s>l'<.ir<<nl v/oik heoeli. The hood device is nut clTtcllve In enmp I I all i ng I lie task. It needs To be redesigned to provide a belter canopy to come down over the work ar. .i, and air ve locity should be increased. II. Air Samples: jij' Air samples were taken to determine.'the presence of contaminants in the laboratory. Results ore nttaehed. Based on the ait ached data, the greatest potential Cor overexposure to vapors would lie due to occasional high levels of vinyl chloride. The t lircs'iol d limit value (average, daily, H-hour, acceptable ixposurc limit) for this vapor is 500 ppm. The data dots not indicate a constant high level exposure this ;nat. < mwiaiu t. ':l John Mayfield - 2 October 25, 1968 jf'-V it should be^'powited. out,'howbycr;, that a dailyy r exposure even ifor A shorter tim$.perodj to concern rations such as, the 1340 ppm recorded bn 10y|ho8, might br a potential s**'.problem. This should.be Investigated, to determine whether or not this level of vapor concentration Srs a doily occurrence; connected with the work rout ire and the lack of proper ventilation. DJC/lam Attachment D. J. Celley Industrial Hygienist , ,u:.; ,n; . j -r-.4^4:1 >* 11 '* r: - i .! ' 1 ..vi. v* ' i* ! MttC : p. c. Coy, M.h. -2- July 15, l'JVG 4. Jit juimiwiry, Mr. Muchun/m h;t luid sioitip ioh;i,;fprimarily M/icf 1 fllKl M< * I /I 1 f'.iJlt intj, WlHMi! 1 l<r W/lfl polciil (ally MXpOJiMtl to Mmu nolr.e U'Vcl II ifXfM-iMl i | m | *1 () ||i mm rdln Mtiiinj ComprohMCtl yi i i (n Mnu \ Jtrio <41(*.(m, iihI V/<*i*i im| ikwit I he iiilo- i ........ .......... 1 i 11* 11 * l * Ml ( 111 i 4 * I 1 ,1 I \ M 1*1 I (t It ( <-UM Niil( li t.t.L Ml,II * VJ ; ... . . ^'; *h; ,i v* i , s' -r * :'\v' _ ;.V !;ik; ' :- D;: ' .:, -V ii-^-68 -V.' co--nt.a..m....in...a..n...t.. !: ' ^^>8:25' AM : 9-16-68 , 2V20 PM 9-27-,fc&f' *! 10:20 AM': 10-3-68 8:15 AM 1.1.1-Trichlaroethane: . ?* 0/5 1.1.2-Trichloroet'hane 1.-0 1.1.1.2-Tet'raehldroe thane <0.7 1,1-dichloroethane Trichloroethylene 4$V Vinyl chloride and/or* Ethylene dichloride 80.0 Vinylidene chloride 3.0 Ethyl chloride Methanol Ethane Ethylene Pcrchloroethylene <0.8 Freon 12 Unknown <1.0 <0.8 <0.5 : <1.0 m4;oo , ' ; 1.0 3.0,.t ; A-f 5-51#. :w' - 80.0 50.0 2.0 120.0 4.0 '1340.0 -3.0 4.0 jU; M2: r ` |- i~~ R&S 020571 Si? MC/lam H'eS^afecty aand Loss Prevention 10-29-68