Document pBLkbX5QKENkkRrLbZmYJ16LB

GRACE To: D. D..Walczyk From: H. 6. Cummings cc: R. C. Deskin F. W. Eaton R. R. Lyons S. Venuti J. W. Wolter* Construction Products Division Date: May 27, 1987 Subject: Airborne Fiber Studies for the Attic Wetting Method and the Pluronic Wetting Agent jj- \ PLAINTIFFS { EXHIBIT j WRG-1026 Splitter tests were conducted during April to study the effect of an alternative wetting method and the addition of a wetting agent (Pluronic L-62) on the airborne fiber levels generated by Terralite. The test objectives are defined in a memorandum, "Respirable Fiber Control Development Plan"; D. D. Walczyk to R. C. Deskin; February 4, 1987. 1. Wetting Methods Analysis of the splitter tests results was done to compare the alternative wetting method (the Attic Method) to the current method (the Fortified Method). The Attic Method sprays the water in the bag instead of on the belt. a) -L----2----T--e---r-r-a---l-i-t-e----w--/-3--#---H- 2~0 The splitter test results for the L-2 Terralite show a 93% statistical probability that the Fortified spray method generates lower airborne fiber levels than the Attic Method does. Spray Method f/cc Average Std. Dev. Fortified ll H 0.145 0.167 0.123 0.145 0.022 Attic II ll 0.195 0.180 0.190 0.188 0.008 10003106 D. D. Walczyk May 27, 1987 Page 2 1. Wetting Method (cont'd) b. L-3 Terralite w/6# H,0 Statistical analysis of the splitter test results for the L-3 Terralite shows the two spray methods generate airborne fiber levels that are not significantly different from each other. Spray Method f/cc Average Std. Dev. Fortified " " 0.261 0.337 0.372 0.323 0.057 Attic " " 0.315 0.261 0.353 0.310 0.046 2. Wetting Agent Statistical analysis of the splitter test results shows a 98% probability that the material with Pluronic L-62 generates a higher airborne fiber level than the material without it. The material used was L-2 Terralite with 3# HgO sprayed by the Attic Method. Treatment f/cc Average Std. Dev 3# H,0 ^II If 0.195 0.180 0.190 0.188 -0.008 3# Hc~0 w/Pluronic ii II 0.205 0.236 0.261 0.234 0.028 10003107 D. D. Walczyk May 27, 1987 Page 3 2. Wetting Agent (cont'd) A comparison was also done using L-3 Terralite with 6# H20 versus 3# H20 and Pluronic. The L-3 without the Pluronic generated a fower airborne fiber level. Treatment f/cc Average Std. Dev 6# Hli 20 0.261 0.337 0.372 0.323 0.057 3# H2O w/Pluronic It 0.491 0.592 0.586 0.556 0.057 HGC/sy H. G. Cummings 10003108