Permit to work in construction

Most of the time a risk assessment and method statement is enough control for a task. For a smaller number of high risk activities, a site adds a permit to work: a formal check and sign-off that the specific precautions are actually in place before anyone starts, and that the area is safely handed back afterwards. This guide explains what a permit to work is, when a UK construction site uses one, and what a good permit contains.

What a permit to work is

A permit to work is a documented control for a defined high risk task. It does not do the risk assessment for you. It sits on top of the RAMS and confirms, in writing and with named signatures, that the precautions identified in the RAMS have been put in place for this specific job, in this specific location, for a specific window of time. It names who may do the work, sets the conditions, and is cancelled and signed back on completion.

When a construction site needs a permit to work

Permits are reserved for activities where getting the control wrong could be serious or fatal. Common construction permit types include:

• Hot works permit for welding, cutting, grinding and anything producing heat, sparks or flame, with fire watch and post work checks.
• Confined space entry permit for tanks, chambers, deep excavations and other spaces with a risk of a hazardous atmosphere.
• Electrical permit for work on or near live systems, tied to safe isolation and lock off.
• Excavation or dig permit confirming services have been located and the dig is controlled.
• Work at height or roof permit for higher risk access, and lifting permits for crane and lifting operations on many sites.

The principal contractor usually decides which activities on their site require a permit and runs the permit system.

What a good permit to work covers

A permit that actually controls risk includes:

• The exact task and location, not a general description.
• The hazards and the specific precautions required before work starts, drawn from the RAMS.
• Isolations and lock offs in place, for electrical, gas or mechanical energy.
• The people authorised to carry out the work and their competence.
• A start time and an expiry, so a permit cannot silently run past the conditions it was issued under.
• Sign-off to start by the authorised issuer and sign-off to hand back by the person in charge of the work.
• Cross reference to any related permit, for example a hot works permit inside a confined space needing both.

How the permit fits with the RAMS

The chain runs one way. The risk assessment identifies the hazards and controls. The method statement sets out how the task is done using those controls. The permit to work then confirms, on the day, that those controls are in place for this specific job and time window, and formally authorises the start. A permit with no supporting RAMS behind it is a red flag, and so is a high risk task with a RAMS but no permit on a site that requires one.

Where permits go wrong on site

• Permits issued as a paperwork exercise without the issuer checking the precautions on the ground.
• No expiry, so work continues after conditions change.
• No sign back, so nobody confirms the area is safe again, a common cause of hot works fires that start after the crew leaves.
• Overlapping permits not cross referenced, for example hot works in a confined space.
• The permit not matching the actual task because the job changed after it was issued.

Frequently asked questions

What is a permit to work?

A permit to work is a formal, documented control for high risk activities. It records that the specific precautions are in place, names the people authorised to do the work, sets the time limits and conditions, and is signed off both to start and to hand the area back. It is a control on top of the RAMS, not a replacement for it.

When does a construction site need a permit to work?

For higher risk activities where a failure to control the risk could be serious, such as hot works, confined space entry, work on or near live electrical systems, excavation near buried services, and certain roof or height work. Many sites also permit lifting operations. The principal contractor usually sets which activities need one.

Who issues and receives a permit?

An authorised issuer, competent in the activity, checks the precautions and issues the permit. The person in charge of the work receives it, confirms they understand the conditions, and signs it back on completion so the area can be returned to normal use.

Is this legal advice?

No. This is a plain-English working summary to support site teams. Permit arrangements should follow your site rules, the principal contractor's system and relevant HSE guidance for the activity.

Related guides: RAMS for excavation, COSHH assessment, and the CDM 2015 regulations explained pillar.