- Standard Number:
OSHA requirements are set by statute, standards and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website at https://www.osha.gov.
September 28, 1977
|MEMORANDUM FOR:||JACK D. TORREY
Acting Regional Administrator Region VIII
|THRU:||DONALD E. MACKENZIE
|FROM:||RICHARD P. WILSON
Deputy Director, Federal Compliance and State Programs
|SUBJECT:||Interpretation of 29 CFR 1926.800(c)(2)(vi) line 5 "shall be withdrawn".|
If 1.5 percent or higher concentration of flammable gas is detected in air returning from an underground working place, the employees shall be withdrawn from the tunnel and away from the portal. The power shall be cut off to the portion of the area endangered by such flammable gas until the concentration of such gas is reduced to 1 percent or less.