Permit to Work (PTW): the Form and the System

Use the form below: select the work type, and the tool shows the controls for that type — the isolation, the gas test (with the live limits for the confined space), the area and the people, the time, the emergency. The 20-point system audit below is the check that the PTW system itself is working — the procedure, the training, the log, the review — because the form is only as good as the system around it.

How to use the tool

1. Select the work type — hot, confined space, electrical, working at height, or the general (cold) work
2. Complete the permit header — the number, the area, the issuer, the receiver, the start and the end time
3. Work the controls for the type — the isolation, the gas test, the gas limits, the emergency, the specific controls the type requires
4. Issue the permit — the issuer signs, the receiver signs, the permit is posted at the location and logged
5. Close the permit — the work complete, the area checked, the permit cancelled and returned; the system audit below checks the whole cycle

Worked example

A hot-work permit on the storage tank farm: the issuer the area supervisor, the receiver the welding gangs foreman, the area the tank 4 bund. Controls: the tank isolated (the blind fitted, the valve locked, the blind certificate), the gas test at the point of work — O2 20.9, LEL 0, CO 2, H2S 0 — all within limits, the fire watch appointed with the 2 kg and the 6 kg, the drip tray, the 15-metre radius cleared of the combustibles, the fire brigade briefed, the emergency the muster and the alarm. Time: 08:00–16:00, the permit valid one shift, the extension by re-issue, not by a tick. Close: the work complete at 15:10, the area cooled and checked for 30 minutes (the smoulder check), the permit cancelled and returned, the log updated. The audits 20 points are the check that this cycle, repeated 200 times a year, holds at the 200th.

Standard & legal context

The PTW is the standard high-risk control in the UK (the HSE process safety practice, the HSG100 and the INDG family), the US (the OSHA process safety standard 1910.119 references the PTW as the standard control, and the HAZWOPER 1910.120 requires the authorisation for the confined space and the hot work in the HAZWOPER universe), and the oil and gas industry worldwide (the API and the ISO practice). ISO 45001 risk control and the MOC sit on the same logic. The form below is the industry pattern with the gas limits from the UK and US practice.

Common mistakes

1. The rubber stamp — the permit signed at the office without the area check is the document the investigation quotes back at you
2. The extension by the tick — the permit is valid for the shift stated; the extension is a re-issue with the re-test, not a line added
3. The gas test once, at the start — the confined space is tested before and during, and the hot work is re-tested on the change; the single test is the one that misses the drift
4. No log, no review — the PTW system is audited: the log of the permits issued, the training of the issuers and the receivers, and the periodic review of the system; the 20-point audit below is that review