Except for safety pressure relief valves, no owner or operator of a petroleum refinery shall install or operate a valve at the end of a pipe or line containing volatile organic materials unless the pipe or line is sealed with a second valve, blind flange, plug, cap or other sealing device. The sealing device may be removed only when a sample is being taken or during maintenance operations.
Ill. Admin. Code tit. 35, § 215.451
Amended at 7 Ill. Reg. 1244, effective January 21, 1983