As many continue the debate around energy isolation methods associated with entry into a Permit-Required Confined Space, I offer another example of why getting the energy isolation plan RIGHT is SO IMPORTANT. I know there are safety professionals out there who feel strongly that single valve isolation or the use of an “automated valve” being controlled by a PLC is perfectly safe and compliant; but this incident can at least provide a first-hand account of how an improper energy isolation plan, which utilized a single UNLOCKED block valve and an AUTOMATED valve on a liquid Anhydrous Ammonia (NH3) line feeding a “dryer” injection system. Here is the incident summary of this tragic accident…
