Future requirements for unrestricted entry into confined spaces


  • Charles L. Keller

    1. Association of American Railroads Washington, D.C. 20001
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    • Charles Keller is a graduate of the U.S. Coast Guard Academy, class of 1960, and received a Master of Science degree in Physics from the U.S. Naval Post Graduate School, Monterey, CA. He spent twenty years in the U.S. Coast Guard as a commissioned officer, the last eleven involved with the transportation of hazardous materials by water. After retiring from the U.S. Coast Guard in 1980 he went with the National Fire Protection Association in Quincy, MA to head up their certification program for marine chemists. In February of 1985 he went to work for the Association of American Railroads as Director, Hazardous Materials Systems (BOE), the successor to the Bureau of Explosives.

  • The author was an employee of the National Fire Protection Association when this speech was prepared.


An overview of the current requirements for confined spaces. Special attention is given to the toxic levels and applicability of the threshold limit values to the requirements for entry into confined spaces.