Permit to workPTW

A permit to work is the formal authorisation that high-risk work cannot start without — hot work, confined-space entry, working at height, energy isolation, excavation, and critical lifts are the categories a permit-to-work system governs. The permit is a document and a workflow: it captures the scope, the isolations, the gas tests, the fire watch, the standby attendant, and the controls agreed between the requestor, the authorising person, and operations, and it requires a named signatory to accept the controls before the first step. The permit is also the record — it is retained as audit evidence that the work was planned and authorised, not improvised.

The failure mode of a permit system is the permit-as-paperwork — a form filled in to satisfy the auditor after the work was decided. A permit-to-work system that works isolates the energy before it authorises the work, sequences the approvals so no one can skip a step, and closes the permit with a return-to-service sign-off so the isolation is released by the person who applied it. OSHA treats the permit-required confined-space standard (29 CFR 1910.146) and the lockout/tagout standard (29 CFR 1910.147) as the backbone, and the permit is where those controls are documented at the workface. See lockout/tagout, confined space, and job hazard analysis.