Operational guide · Registers & logbooks

Permit to Work System

A Permit to Work is the documented method by which the SMS controls high-risk work under the applicable procedure and risk assessment.

permit to workhot workcold workISM par. 7

Operational Explanation

A Permit to Work is a documented method adopted by the SMS to control high-risk work. ISM §7 requires procedures for key operations but does not prescribe one PTW model, seven categories, or universal thresholds and durations.

Regulatory Reference

ISM Code §7: the Company establishes procedures, plans and instructions for key operations. Categories, atmospheric limits, signatories and validity derive from risk assessment, SMS and applicable sector guidance. SOLAS III/19.3.6 concerns entry and rescue drills, not the source of an enclosed-space permit.

A permit documents controls already verified at the worksite; it does not replace risk assessment, energy isolation, verification of zero energy, monitoring, supervision and coordination of simultaneous work. Before reinstatement check people, tools, safeguards and handback of the system. National practical guidance, to be applied in its proper context: MCA COSWP 2026.

Scope of Application

Work subjected by the ship's SMS to PTW control according to risk, ship, cargo, location and applicable guidance; there is no uniform IMO list of seven permits.

Procedure / How to Complete It

Identify the work and applicable SMS procedure.
Apply thresholds, signatories, validity, isolation and monitoring required by company procedure and relevant guidance.
Suspend and reassess when conditions, people or scope change.
Close the permit and restore the system under the procedure.

Practical Example

Example: for hot work, atmospheric limits, signatories, fire watch and validity are taken from the SMS procedure and applicable guidance; the permit is suspended if conditions change.

What Typically Goes Wrong

A signed permit with controls not verified at the worksite gives false assurance. For hot work also consider adjacent spaces, heat transfer, combustible materials and subsequent fire watch. Atmosphere testing is one necessary control where applicable, not sufficient assurance on its own.

Common Mistakes Mistake Library

Mistake	Consequence	How to avoid it
Hot work permit renewed without a new atmosphere test if the work extends beyond the initial validity	Risk conditions not updated, possible accident with an atmosphere that has changed in the meantime	Always repeat the atmosphere test when renewing a hot work permit
Multiple permits active at the same time without checking their mutual interactions	Unforeseen risk combinations (e.g. hot work and bunkering in the same area)	Always check all active permits before authorising a new one
Cold work in a hazardous area started without assessing the controls required by the SMS	Activities with real risks (e.g. painting in a confined space) carried out without adequate controls	Always apply the SMS risk assessment and controls; use a formal PTW where the SMS or applicable sector guidance requires it

What the PSCO Checks

Port State Control Officers (PSCOs) may request to see active work permits during the inspection, especially if maintenance work is under way on board, checking the consistency between the permit issued and the operational conditions observed.

Operational Tips

Always repeat the atmosphere test when renewing a hot work permit, don't rely on the initial test.
Always check the interaction between all active permits before authorising a new one.
For cold work in hazardous areas always apply the SMS risk assessment and controls; use a formal PTW where prescribed.

Preparation checklist

SMS procedure and risk identified
Thresholds and signatories taken from applicable source
Validity and reassessment defined
Isolation and monitoring checked
Close-out and restoration documented

FAQ

What is the maximum validity of a hot work permit?

Validity is set by the applicable procedure and stated on the permit. Do not assume 12 or 24 hours is a universal duration or permission to continue: changed conditions, interruptions and handovers require suspension, reassessment or renewal under the SMS and applicable requirements.

Does cold work always require a formal permit?

Not under a universal IMO model. In a hazardous area, the risk assessment and SMS controls always apply; a formal permit is required where the SMS or applicable sector guidance requires it.

Who typically authorises a work permit on board?

The competent person designated by the SMS procedure for that work and area authorises it. Distinguish authorisation, execution, atmosphere checks and isolations; do not infer signing authority from rank alone. Transfer of responsibility must be explicit and documented.

Permit to Work System

Operational Explanation

Regulatory Reference

Scope of Application

Procedure / How to Complete It

Practical Example

What Typically Goes Wrong

Common Mistakes Mistake Library

What the PSCO Checks

Operational Tips

Preparation checklist

FAQ

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