#	Letters of Interpretation
1	05/08/2025 - 1910.1051(g)(5)(i) - Engineering controls under the Benzene and 1,3-Butadiene standards
2	05/08/2025 - 1910.1051(f)(2)(ii) - Engineering controls under the Benzene and 1,3-Butadiene standards
3	12/07/1999 - 1910.1051(d)(1)(iv) - Exposure monitoring requirements under the coke oven emissions standard
4	10/06/1995 - 1910.1051 - 8-hour total weight average (TWA) permissible exposure limit (PEL).