Document 6w34GGwnVeL1NLwd7qoBrav7E

-ttol3M 1110-16 Roa Fruit* Colorado 8152' 303 858-3654 March 1, 1979 We have enclosed a copy of our Pabco Technical Bulletin PTB-48-7A, "Asbestos Identification in Old Calsil Insulation". This bulletin updates and replaces PTB-48-7. Please remove this prior issue from your files and substitute the up to date information. Thank you. PABCO INSULATION DIVISION mtc Enclosure DUP H537I3 DU 062020 PTB-48-7A February 15, 1979 Replaces PTB--i?-" ASBESTOS IDENTIFICATION IN OLD CALSIL INSULATION* Because of the health hazards involved in working with asbestos, it is essential that old asbestos-containing calsil be properly identified to avoid accidental worker exposure-curing maintenance or removal procedures. Prior to the early seventies, all calcium silicate insulation, and several other types as well, contained asbestos as the reinforcing fiber. Most of the asbestos used was chrvsotile, but other types such as crocidolite and amosite were also used. All are hazardous to health. Since the early seventies, all manufacturers have switched to either glass or organic fibers for reinforcement. Because of the refractory nature of asbestos fibers, they are not destroyed by the flame from a propane (Bernzomatic) torch. Rather, they glow as little incandescent rods in the propane flame. Since the newer fibers -- glass, rayon, polyester, cotton, etc. -- are destroyed by the propane flame, this provides an easy means of positive identification for asbestos. The simple procedure is as follows. 1. Break a small piece of insulation off a section of calsil. 2. Heat the broken surface with the flame from a propane torch. 3. Observe. Figure 1 shows asbestos-containing material. The material in Figure 2 does not contain asbestos. 4. With some experience, a good worker can break off a chunk of insula tion and tell by eye whether or not asbestos is present. A small magnifier makes the process even simpler to carry out. *N0TE: Since December, 1978, the Pabco Division started to mark all of their Super Caltemp production with an identifying green strioe that shows it is asbestos free. "The technical cm* shown are conuoerea Dv us to bt accurate ana reuaote however no warranties express or imphM are given or mtenaea ana any sucn warranties are expressly aisciaimeo. ' DUP 1 15371-4 PABCO INSULATION DIVISION Louisiana-Pacific Corporation 1110 16 Road Fajita. Colorado 81521 DU 062021 ; MiaJMtSll-Mliii i!i -1 x.:. PTB-48-7A Page No. 2 Figure No. 1 Appearance of asbestoscontaining insulation in propane flame. Asbestos fiber does not melt and shows up as little glowing rods in the flame. aoMi DUP 1153715 DU 062022