OSHA Answers Questions about Compressed Gas Cylinders
In a May 23, 2008, Letter of Interpretation posted to OSHA's Web site Dec. 4, the agency answers questions about the standards that are applicable to handling, using, and storing compressed gas cylinders. The inquiries regarded two different compressed cylinders used for laboratory calibration of gas detectors, one cylinder containing 100 percent methane and the other containing 20.9 percent oxygen and 79.1 percent nitrogen.
OSHA says that the handling, use, and storage of compressed gas cylinders in applications other than welding and cutting in general industry workplaces is governed by 29 CFR 1910.101, Compressed gases standard. Under Section (a) of the standard, the agency requires that gas cylinders be visually inspected to determine that they are in safe condition. The standard further states, under Section (b), that "the in-plant handling, storage, and utilization of all compressed gases in cylinders . . . shall be in accordance with Compressed Gas Association (CGA) Pamphlet P-1-1965."
The agency notes that there are more recent versions of the industry consensus standards that are referenced in §1910.101. If the more recent consensus standards address hazards associated with compressed gases that are not addressed in the CGA pamphlets referenced in the standard, §1910.101, §1910.1200, or any other applicable OSHA standard, the more recent consensus standards may provide support for a citation alleging a violation of the OSH Act's general duty clause. The agency also says that if an employer is not in compliance with the requirements of an OSHA standard but is complying with the requirements of a current consensus standard that clearly provides equal or greater employee protection, the violation of OSHA's requirement will be treated as a de minimis violation, which is a violation that has no direct or immediate relationship to safety and health and results in no citation, penalty, or requirement to abate.
In the letter, OSHA clarifies that a cylinder that contains 20.9 percent oxygen and 79.1 percent nitrogen, which is essentially compressed air, presents no greater oxidation hazard than that of the atmospheric air already present in the workplace. Therefore, the cylinder containing 20.9 percent oxygen would not be considered an oxygen cylinder or an oxidizing compressed gas for the purposes of 29 CFR 1910.101.