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Demystify: 

GREAT ANSWER, John.  I've printed it out.  But I'm confused because clearly, I shouldn't put my workers in N95s if, say, the dust is way over 5X the TLV unless they are just running through the workplace and out the other side!   The mask wouldn't last long at high concentrations.

We have situations where they throw powdered mineral dusts into floor fans all day while shooting a scene that is supposed to be taking place after an explosion or in a sand or dust storm.  (Think: Planet of the Apes as an example.)  We've had workers permanently disabled with lung fibrosis in two days shooting like that.

And add to these facts that even scenes that look like they were shot outdoors, may well have been shot indoors in a studio.  That dust can be in extremely high concentrations in order to get the shot to look right.

The old 5X the TLV rule was very useful because I could do a guessimate of concentration from the weight of the material they hurl at the fan/hour and then nix the N95s.

I need some nice simple statement that even Producers could understand like the old 1995 rules to do two things:
1.  eliminate any dusts with really low TLVs for this purpose
2.  get the Producer to upgrade to cartridge or full face in heavy dusts--at least for the crew (actors are expendable, I guess).

I've told them they need to do air monitoring during these shoots, but a) that's not going to happen, and b) it wouldn't be useful even if they did it.  The reasons are that the concentrations of dust vary greatly all over the space and the pumps cannot be on during shooting due to the purr they add to the sound track.  And you can't put personal monitors on the actors at all, yet they are the ones the dust is aimed at.

I need similar strategies for isocyanates in two-component urethane resins and paint spraying without a booth, lead fume when they blow up a car with lead azide (makes a nice black smoke), and the like.  Just think of ideas you might have for some backward third world country, because that's about where we are.

Monona

In a message dated 1/27/2011 8:36:40 PM Eastern Standard Time, jbcallen**At_Symbol_Here**MMM.COM writes:

In the discussion on the subject topic, Peter Zavon's and Michael J. Wright's information and/or comments about surgical masks versus NIOSH 42 CFR 84 certified respirators and/or health care respirators/surgical masks for voluntary and/or routine use are correct; however, concerning the selection and use of NIOSH certified Filtering Facepiece Respirators (FFRs), several of you are providing information that is either hearsay, technically incorrect and/or outdated.

Monona's statement below regarding the use of a HEPA Filter for substances having an Occupational Exposure Limit (OEL), e.g., PEL or TLV, <0.05 mg/m3 (i.e., toxicity equal or greater than lead) and which formed the basis of NIOSH 30 CFR 11 and selection and use of respirators per OSHA became null and void with the advent of NIOSH 42 CFR 84 in 1995 and the revisions to the OSHA Respiratory Protection Standard, 29 CFR 1910.134 in 1998.  Today, employers do not select filters based upon the OEL.
Except for certain OSHA Substance Specific Health Standards (general industry and construction) which call out the use of HEPA Filters (N100, R100 or P100) for respiratory protection (As, asbestos, Cd, cotton dust where CONC >10 X PEL, Pb and 4,4,-methylenedianiline), the selection of filters is dependent upon whether when non-oil and/or oil-based particulate matter (aerosols) are present and filter efficiency is not specified, e.g., Cr(VI).
Although N95 FFRs are the most widely used, FFRs are not just those with a Classification as N95. They can be N99 or N100, R95, R99 and R100 as well as P95, P99 and P100.
The use of N95 FFRs <5 x OEL (PEL) applies only to the Cotton Dust Standard.  Per the Assigned Protection Factor (APF) Table 1 in the OSHA Respiratory Protection Standard, 29 CFR 1910.134(d)(3)(i)(A), FFRs are half facepieces and have an APF =3D 10 as do elastomeric (rubber-type) half facepieces.

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