Archived Newsletters
Cal/OSHA Proposed PEL for n-propyl bromide, Part 1 - PEL and Consequences
Barbara Kanegsberg and Ed Kanegsberg
Enforceable PEL
A California OSHA (Cal/OSHA) proposal would amount to an operational ban on the use of n-propyl bromide (nPB, 1-bromopropane) for most critical and industrial cleaning activities. The proposed Permissible Exposure Limit (PEL) of 5 ppm is scheduled for possible approval at a March 19, 2009 Standards Board meeting in Costa Mesa, CA. Other chemicals may be of interest to you (please see Part 4). Given the utility in industrial and precision cleaning, we are emphasizing nPB.
Cal/OSHA PEL’s are legally-enforceable throughout California. It is reasonable to expect that the exposure limit would influence industry and legal advisors nationwide. Cal/OSHA has a new, improved PEL process; nPB and the other compounds under consideration on the 19th were not evaluated using the new, improved process.
Significance
The proposed PEL of 5 ppm airborne exposure for nPB does not ban its use in critical cleaning applications. However many consider that such a PEL will essentially end most nPB use in critical and industrial cleaning applications because 5 ppm is not readily or consistently achievable even in well-controlled open-top degreasing systems.
In fact, nPB has been a viable option for vapor degreasing for some time. nPB was approved as acceptable substitute for ozone depleting chemicals in metals, electronics, and precision cleaning through the EPA SNAP (Significant New Alternatives Policy) Program. This finding of acceptability is important because, in the past, where there have been great concerns about the safety of a proposed substitute, the EPA has declared a proposed chemical to be unacceptable. You should be aware that nPB was proposed to be unacceptable in aerosol and adhesive applications, because it is more difficult to control emissions in those applications. The information on both the degreasing rule and proposed aerosol and adhesives rule is available in the Federal Register.
Consequences
What are the consequences? A very low Cal/OSHA PEL may impair your ability to achieve reliable production. You don’t use nPB? Check your supply chain. Changes in cleaning processes, including changes by your suppliers, can result in an unintended, negative, domino effect. Proposed substitutes for nPB must be evaluated in terms of product performance and reliability, environmental impact, worker safety, and costs.
In our experience, using airless or vacuum systems can markedly decrease air emissions of chemicals. However, such equipment requires a significant up-front capital investment; and there are on-going costs. If production costs for components manufacturers increase due to regulatory compliance equipment costs, chemical distributors and suppliers might reduce production quantities, thus driving the total cost even higher.
It is not realistic to expect that chemical companies will come up with substitutes or “synthesize around the problem.” Developmental costs, including regulatory considerations, have resulted in an overall decrease in the development of aggressive (or even assertive) cleaning agents.
A new ,improved, better PEL process
In our opinion, adopting a Cal/OSHA PEL for nPB based on the current recommendations would be an ill-advised. It would be more protective of workers, more defensible by Cal/OSHA, and more understandable to industry for a Cal/ OSHA PEL for n-propyl bromide to be developed by the recently-established Cal/OSHA PEL process. This process includes definitive risk assessment by a Health Expert Advisory Committee (HEAC) and feasibility assessment by a Feasibility Advisory Committee (FAC). The assessments are formal; the discussions are public.
We have followed the development of the PEL process; and we have provided comments to Cal/OSHA. Barbara has attended pertinent public meetings on a regular basis. It is a process you should support.
Resources, References
Cal/OSHA Standards Board Meeting, March 19, 2009
https://www.dir.ca.gov/oshsb/airborne_contaminants09.html
Link to ISOR (Initial Statement of Reasons)
https://www.dir.ca.gov/oshsb/airborne_contaminants09_ISOR.pdf
Cal/OSHA Standards Board home page
https://www.dir.ca.gov/oshsb/oshsb.html
Cal/OSHA PEL Process, Health Expert Advisory Committee
https://www.dir.ca.gov/dosh/DoshReg/5155Meetings_2009.htm
EPA SNAP Final and Proposed Regulations for n-Propyl Bromide
http://www.epa.gov/ozone/snap/solvents/2007nPBRegsQA.html
Clean Source Article, SNAP and nPB
n-propyl bromide, acceptable in solvent cleaning
