As most of you know, PRCS Entry is one of the specific SWPs called out in the PSM and RMP standards. But many programs fail to meet 1910.146(f)(4), and a recent CSB accident report tied the requirement for canceling a permit to a catastrophic explosion event.
1910.119(f)(4) The employer shall develop and implement safe work practices to provide for the control of hazards during operations such as lockout/tagout; confined space entry; opening process equipment or piping; and control over entrance into a facility by maintenance, contractor, laboratory, or other support personnel. These safe work practices shall apply to employees and contractor employees.
Peeling this onion a bit further, we can see that the PRCS standard (1910.146) REQUIRES procedures (such as closing off a permit space and canceling the permit) necessary for concluding the entry after entry operations have been completed;
1910.146(d)(12) Develop and implement procedures (such as closing off a permit space and canceling the permit) necessary for concluding the entry after entry operations have been completed;
The CSB stated in its report:
The CSB’s investigation found that metal debris punctured a rupture disc, allowing EtO to enter the pressure relief piping. The debris came from portable work lights that had been inadvertently left inside a large reflux drum by workers who had been performing turnaround maintenance activities in the drum in May 2023, a couple of months before the incident. Over the next several weeks, after the Glycol II unit was restarted, the work lights degraded, creating debris that thereafter entered downstream equipment and eventually punctured the rupture disc, which led to the subsequent fire, explosion, and EtO release.