Date: Sat, 4 Dec 2010 15:28:51 -0800
Reply-To: DCHAS-L Discussion List <DCHAS-L**At_Symbol_Here**LIST.UVM.EDU>
Sender: DCHAS-L Discussion List <DCHAS-L**At_Symbol_Here**LIST.UVM.EDU>
From: Michael Cooper <mcooper**At_Symbol_Here**EXPONENT.COM>
Subject: Re: OHSA/NIOSH Permissible limits
In-Reply-To: A

Note that California has a defined process built into their statutes to review and revise airborne OSHA PELs for the State.   California appears to be the only state that does this review and revision on a regular basis using a dual voluntary advisory committee approach.  The process is public and involves all interested stakeholders.  A PEL recommendation is advanced by a Health Expert Advisory Committee and is then reviewed for implementation issues by a Feasibility Assessment Committee.  Not a perfect process, but it does help make California PELs more in line with current literature and industrial hygiene practice than the 1968 based Federal PELs.

As a result, California enforceable PELs are often times lower (significantly) than the Federal OSHA PELs and in some cases California PELs are lower than the ACGIH TLVs.  This should be considered when writing and reviewing MSDS and when setting company occupational exposure limits and action limits.

with regards,


Michael N. Cooper MS, MPH, CIH

Senior Managing Scientist

Exponent® / Failure Analysis Associates

149 Commonwealth Drive, Menlo Park, CA  94025

( TEL +650 688-1760 7 FAX +650 688-1799 CELL +408 313-2127

Email: mcooper**At_Symbol_Here**  

From: DCHAS-L Discussion List [mailto:DCHAS-L**At_Symbol_Here**] On Behalf Of ACTSNYC**At_Symbol_Here**CS.COM
Sent: Saturday, December 04, 2010 9:19 AM
To: DCHAS-L**At_Symbol_Here**LIST.UVM.EDU
Subject: Re: [DCHAS-L] OHSA/NIOSH Permissible limits

Chris, et al.,

Just two more fast comments and then, uncharacteristically, I'll shut up.

1.  Rob asked for documentation about OSHA's opinion of their PELs.  The statement is the Federal Register at 58 FR 35337-35351, June 30, 1993 when OSHA had to formally reinstate the old PELs thus revoking both the upgraded levels and addition of new PELs on substances for which there were no standards in 1968:

"OSHA continues to believe that many of the old limits which it will now be enforcing are out of date (they predate 1968) and not sufficiently protective of employee health based on current scientific information and expert recommendations. In addition, many of the substances for which OSHA has no PELs present serious health hazards to employees."

How I wish you would all add this short paragraph to your explanations of air quality standards somewhere for students to really understand the issue.

2.  Please also let students understand that there is no air quality limit that is not "feasible" no matter how low it is set.  Then the only consideration is money. 

For example, if we have to use a two component urethane system in an open shop, I require the employer put our union workers in air-supplied respiratory protection to keep below the 0.005 ppm TLV for the isocyanates.  Once the employer has spent 4-5 large for the compressors and lines WHICH THEY SHOULD HAVE IN THE SHOP ANYWAY, it only cost about $100 more per employee than air-purifying systems. 

Done well, this system can keep the exposure to essentially zero.  And better yet, the employer can install local exhaust ventilation such as a walk-in sized spray booth.

The only balancing act, then is between money and workers health.  As the old union song goes:  Whose Side Are You On?


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