An independent federal agency investigating chemical accidents to protect workers, the public, and the environment.
Improve isolation on acetylene generator water lines by incorporating a double-block-and-bleed with a vent to a safe location, or other isolation means of comparable effectiveness.
Implement an effective Process Safety Management program, in accordance with OSHA 1910.119. Include written operating procedures and checklists that are understood by the workers responsible for using them. Train workers on the procedures and periodically confirm that they are being properly followed.
Update the OSHA 1910.102 Acetylene Standard (a. Cylinders, b. Piped Systems, and c. Generators and filling cylinders) to remove the existing references to unavailable and obsolete Compressed Gas Association Pamphlets (CGA G-1-1966, G 1.3-1959, G 1.4-1966). As an alternative, consider incorporating by reference NFPA 51A Standard for Acetylene Cylinder Charging Plants.
Immediately inform existing acetylene generator users that the check valve did not prevent acetylene gas backflow in this incident. Recommend interim actions be taken to ensure that Rexarc check valves in service on acetylene production equipment will operate reliably.
Replace check valves of this or similar design supplied by Rexarc with valves that will perform more reliably in recycle water service.
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