February 20, 1986

This is in response to your memorandum on this subject of January 28, 1986. We understand from a reading of your memorandum and telephone conversations with your staff, that Rohm and Haas Company is conducting some processes involving bis-chloromethyl ether and methyl chloromethyl ether in what they designed to be closed systems. According to 29 CFR 1910.1006(b)(4) and .1008(b)(4), a closed system is one that prevents the release of either of the two above mentioned ethers into regulated areas, nonregulated areas, or the external environment. We can see no way to improve upon this definition.

From telephone conversations held since receiving your memorandum, we understand that there are releases of the ethers due to deteriorating seals and packings. Moreover, releases would be greatly reduced by correcting the condition. Given these facts, it must be concluded that the systems, although designed as closed systems, have developed openings and become open-vessel systems. Rohm and Haas Company is thus allegedly violating 29 CFR 1910.1006(c)(3) and .1008(c)(3) which prohibit the operation of open vessel systems.

These releases of the ethers that are occurring due to the deteriorating seals and packings are incidents that must be reported by Rohm and Haas Company in accordance with 29 CFR 1910.1006(f)(2) and .1008(f)(2).