What is a permit to work?

A permit to work is a written form that allows named people to do one particular dangerous job, in one place, for a set length of time. It also sets out the precautions they must take. The Health and Safety Executive (HSE) describes a permit to work system as “a formal recorded process used to control work which is identified as potentially hazardous”.^[1] It is also a way of making sure the managers, supervisors and workers involved all know what has been agreed.^[2]

A permit is more than a signature that says “go ahead”. HSE says a permit “is not simply permission to carry out a dangerous job”, and that issuing one doesn't make a job safe on its own. The job is only safe if the people planning it, supervising it and doing it all follow the precautions written on the permit.^[1]

Which jobs need a permit?

Permits are for jobs where a mistake could kill or seriously injure someone, and where the risks need to be tightly controlled. HSE also warns against using permits for everything, because when they are used for routine work they stop being taken seriously.^[1] On construction sites, the most common permits are these:

• Hot works: welding, cutting, grinding or anything else that produces heat or sparks. HSE's fire safety guidance for construction says that where hot work can't be avoided, it should be controlled by a permit.^[3]
• Permit to dig: digging near buried cables and pipes. HSE's guidance on underground services says a permit system may be needed for particularly dangerous work.^[2]
• Confined spaces, such as manholes, chambers and tanks. The law says nobody may work in a confined space without a safe system of work for it.^[4]
• Electrical work, where equipment has to be switched off and locked off before anyone works on it or near it.
• Some work at height, where the site's rules say so.

HSE's permit guidance lists heat and sparks, dangerous electrical work, confined spaces and work at height among the jobs that should be considered for a permit.^[1] Your site's own rules say exactly which jobs need one and who can issue them, so check at your induction.

How a permit works

1. It is issued. Only someone who has been clearly given the authority to issue permits should do it.^[3] They check the job, the area and the precautions, fill in the permit and hand it to the person in charge of the work.
2. It is accepted. The person in charge of the work reads it, checks that the precautions are in place, and signs to say they understand it.
3. It is displayed. A copy is kept at the place where the work is happening, and another stays with the person who issued it.^[1]
4. It is handed over if the job carries on into the next shift. The next shift must be told about any permits that are still live, and what state the work is in.^[1]
5. It is handed back and closed. When the job is finished, the person in charge of the work confirms it is done and the area has been made safe. The person who issued the permit then checks this and closes it.^[1]

A permit only covers the job, the place and the time written on it. HSE says a hot works permit “should not give blanket authorisations to carry out hot works anywhere on site at any time”.^[3] If the job changes, stop and get a new permit.

What goes on a permit

Every type of permit is a little different, but HSE's list for a hot works permit is a good guide to them all. It says a permit should normally include:^[3]

• Where the work is and what it involves.
• When it will start and how long it will take.
• When the permit runs out.
• The precautions to take before, during and after the work.
• How to raise the alarm.
• Who is in direct control of the work.
• Who authorised the work, and who closed the permit.

Why keep a permit register?

A permit register is a list of every permit issued on site. It shows at a glance which permits are live, who holds them and which have been closed. HSE suggests keeping a log of permits so that live ones aren't forgotten when the shift changes. It also points out that work under one permit can make another job dangerous, so permits that affect each other should be linked. It uses the Piper Alpha oil platform disaster as an example, where work under one permit affected work under another and nobody had linked the two.^[1]

The register is also your evidence. If something goes wrong, it shows who authorised the work and when. Fill in a line as each permit is issued, and complete the line when the permit is closed. The live permits for each area also belong on the daily activity briefing, so the gangs know about them before they start work.