Document EvdN85xrZj7XkmaOBw9Gy0M6b

. ... v.' ;; ' '.-Avv"'J.'v-ir . ;i...-'/,.Ku. !f'c*v^Vf.S gp,284;7^F;A7inala New York Acaiicdemy Ratio or Fibers/co Longer than iOs <430 x Mf) to MPPCr;j&t ..... .. (100x IIMmPpIiNnOoEeRr) RryYfPUiAaNnTt ani> Operation ../-r-vtjrS Ratio of average concentration by operation K: .r.T'jrv iS^xv5?-.T5Vc- ;.; t*'r-.l - 1 I if S V Ratio of grand means 2.1 . . Fibers longer than 10 ft The concentrations of fibers longer than 10 ft determined from the same membrane samples as above was also compared with the particle count by ' , impinger. Table 2 shows the ratios of 10-t ft fibers per ml. to impinger' 'j FtouRC 7. F t than 10s with i counts in mppcf for 0 major operations in four plants. The ratios of aver* age concentrations range from 1.7 to 3.8 by operation and from 1.2 l 4.5 by plant; individual operations are even more variable (one or two samples I ; of impinger t than 10 ft Is .! with extreme ratios can cause a considerable change in the least square* line which best fits the datai. The data exhibit about the aame degree of / ^i ^Not enougl [ scatter indicated in NCURf* 1*5. X>v- counted tor i; Figure 7 shows the cumulative percentage of 10+ ft fiber concentrations' Impinger san v and impinger concentrations. To compare the 10+ ft fiber concentrations bran* filters f with the concentrations by Impinger, the pairs were divided into two' 1- the 10 ft ftbei. groups as before ) filler preparation and carding in one, and spinning, - f than 6 ft P1', twisting and weaving in the other. In both sets of duta, 00 por cent of the (' a 10 pi fiber c . :counts from impinger samples were less than 6 mppcf and In both sets, . j., :$ UO per cent uf the concentration* of fillers longer than 10 ft front llm' +' j membrane filter samples were below IB per ml. I Individual operations hiul f Samples w ' cumulative percentages equal to the percentage below 0 mppcf at 9 to 21 / fibers longer than 10 ft per ml.) (loth methods of analyzing the comparative data suggest that the ratio.;./. trlator of the were compar- sampling m; .. ;............-.......-......... " H, I &09 0 . 'vV>r *>* ^ " PRODUCED BY FORD