Permit to Work and Isolation Policy
v3.4
Purpose. This policy establishes the permit to work system as the control for all work on plant and the rules for isolating, proving, locking and restoring energy sources.
1.Purpose and scope
Plant at a power station carries electrical, steam, pressure, hydraulic, mechanical, chemical, gravitational and stored energy, often in combination. This policy applies to every task on plant at every site by employees and contractors, and to every isolation of a single or multiple energy source.
2.Policy statement
No person will work on plant without a permit to work issued by an authorised permit issuer and accepted by an authorised permit recipient. Every energy source must be isolated, locked, tagged and proven dead, depressurised, drained or restrained before work begins. The control room must control every isolation that affects operating plant.
3.Roles
Permit issuers are shift supervisors and authorised operators. Permit recipients are the tradespeople in charge of the work. Isolators are operators authorised for the energy sources involved. Each person must hold the authorisation for the role and the plant on the authorisation register.
- Permit issuer: plans and authorises isolations and work
- Isolator: applies and proves isolations
- Permit recipient: controls the work and the workers
- Control room: records and approves isolations and restorations
4.Isolation rules
Isolations must be applied at the source, not at a control signal. Each isolation point must carry a lock and a tag. Every worker on the permit must apply a personal lock to the group lock box. Proving must be by test, not by indication, and the test must be recorded.
5.Restoration
Restoration must not begin until every worker has removed their personal lock and the permit recipient has signed the work as complete. The isolator must restore in the sequence on the isolation list and the control room must confirm plant status before it is returned to service.
6.Records and audit
Every permit and isolation will be recorded in the Permit and Isolation Register. HSE will audit permits monthly and will investigate any breach as an incident.