Oh Joe! Thank you so much. My head is so buried in art products I didn't think about the stuff being used by you all. The ACGIH TLV-TWA standard for asbestos is 0.1 f/cc and their TLV-TWA for RCF is 0.2 f/cc. That 0.5 f/cc standard you cite below is the manufacturer's recommended standard. F that.
Interestingly, the 5 members of the Refractory Ceramic Fiber Coalition that set that 0.5 f/cc standard sued ACGIH for setting a lower standard citing bias, since many of their members work for the government which the Coalition considered a "conflict of interest." Of course, the judge pointed out that the 5 manufacturers certainly have a conflict of interest when setting their standard and threw the case out. But that and other delightful machinations by industry cost members like me and extra $200 that year for legal defense.
RCF is just as restricted in the EU with a MAK-2 cancer rating. And RCF will indeed convert to cristobalite if the temperature is high enough.
I fight against it's use in the art department. If it is used, it needs to be enclosed in some way. it must not get airborne, not only because it might exceed the TLV, but because it is a dust that will then settle on surfaces, in ducts, etc., and over time can become a hazard to maintenance and other workers.
Just like the asbestos management program requires, I want all users, maintenance and janitorial workers, and anyone who will be where this material is in place to be fully informed about it's presence and it's status as a carcinogen.
In a message dated 10/12/2012 1:17:10 PM Eastern Daylight Time, Joseph.Damiano**At_Symbol_Here**CONTR.NETL.DOE.GOV writes:
Ralph, I believe Moldatherm is a refractory ceramic fiber (RCF) based insulation. RCF will convert to cristobalite with prolonged exposures to high temperatures. Cristobalite is a form of crystalline silica, an OSHA regulated carcinogen. On the other hand, RCF itself is classified as carcinogenic (IARC-2B, NTP-2, ACGIH A2) with a recommended occupational exposure limit of 0.5 fibers per cc. Consideration should be given to whether friable RCF insulation is made airborne during routine furnace operations. Depending upon the scale of the furnace and its condition, the exposures might be associated with loading or withdrawing samples, or fibers entrained by the hot air. RCF suppliers and likely OSHA and NIOSH as well provide guidance on strategies and methods for minimizing exposure during equipment servicing.
Joe Damiano, URS / NETL / DOE
Previous post | Top of Page | Next post