What Is a Permit-to-Work System? A Plain-English Guide

If you run a small construction or maintenance business in the UK, you have probably heard the phrase "permit to work" at some point. Maybe a principal contractor asked if you have a PTW system. Maybe an HSE inspector mentioned it during a site visit. Or maybe you just know your current approach — a verbal agreement and a handshake — is not going to cut it forever.

This guide explains what a permit-to-work system actually is, when you are legally expected to use one, and how to set one up without spending thousands on consultants.

What is a permit to work?

A permit to work (PTW) is a formal written document that authorises specific people to carry out specific work, at a specific location, during a specific time window. It is not a risk assessment (though it references one). It is not a method statement. It is a controlled authorisation that says: "We have checked, and this work can proceed safely under these conditions."

The HSE describes it as "a formal recorded process used to control work which is identified as potentially hazardous" (HSG250).

Think of it like a flight checklist. A pilot could probably take off from memory, but the checklist exists because skipping a step has catastrophic consequences. A permit works the same way for high-risk tasks on site.

When do you need one?

You do not need a permit for every task. Permits are for work where the hazards are serious enough that normal controls (PPE, toolbox talks, method statements) are not sufficient on their own. The most common scenarios in UK construction and maintenance are:

Hot work

Any work that produces sparks, flames, or heat — welding, cutting, grinding, brazing, or using a blowtorch. Hot work is one of the leading causes of construction fires. A hot work permit ensures fire precautions are in place before the work begins and a fire watch continues after it finishes. Our free hot work permit template walks through each section of a typical permit.

Confined space entry

Entering tanks, vessels, sewers, pits, or any enclosed space where the atmosphere could be hazardous. The Confined Spaces Regulations 1997 require a safe system of work, and a permit is the standard way to document it. Gas testing, rescue plans, and atmospheric monitoring are typically recorded on the permit. See our confined space permit template for a section-by-section breakdown.

Working at height

While not every working-at-height task requires a permit, high-risk scenarios — erecting scaffolding, working near fragile roofs, or operating above public areas — often do. The permit records that the access equipment has been inspected and fall protection is in place. Our working at height permit template covers the key checklist items.

Electrical isolation

Work on or near live electrical systems, or isolating circuits before mechanical work begins. The Electricity at Work Regulations 1989 require that equipment is dead and isolated before work starts. The permit records who isolated what, where the lock-out is applied, and who is authorised to work. Our electrical isolation permit template covers lock-out/tag-out procedures.

Other scenarios

Excavation near buried services, roof work, demolition, work near water, and breaking into pressurised systems can all warrant permits depending on the risk.

What goes on a permit?

A good permit-to-work form includes:

• Description of the work — what is being done, and where
• Hazards identified — referencing the relevant risk assessment
• Precautions required — isolation, gas testing, fire watch, barriers, PPE
• Checklist — has each precaution actually been completed?
• Time window — the permit is valid from when to when
• Signatures — the person requesting the work, and the person authorising it
• Close-out — confirmation that the work is finished and the area is safe

The signature part is critical. A permit is not a form you fill in by yourself. It requires at least two people: the person doing the work (or their supervisor) and the person authorising it. This dual-control mechanism is the whole point. It forces a conversation about safety before the work starts.

Paper vs digital permits

Traditionally, permits are issued from a carbonless copy book kept in the site cabin. The top copy goes to the person doing the work, the carbon stays in the book. This works, but it has real problems:

• Permits go missing. They blow away, get rained on, or end up crumpled in a van.
• Approvals are slow. If the authoriser is on another site, you wait.
• Audit trails are weak. When HSE asks to see your permits from last Tuesday, can you find them?
• Handwriting is illegible. This is not a joke — it genuinely causes problems during investigations.

Digital permit systems solve these issues. Permits are created on a phone or tablet, approved instantly via notification, stored permanently, and exportable as PDFs. The audit trail is automatic and time-stamped.

For small contractors, the barrier has historically been cost. Enterprise PTW software costs hundreds or thousands per month and requires training and onboarding. That is changing. Tools like PermitPad offer self-serve digital permits from a free plan, with flat-rate pricing designed for teams of 1 to 50.

How to set up a PTW system

If you do not currently have a permit-to-work system and want to start one, here is a practical approach:

1. Identify which tasks need permits. Start with the big four: hot work, confined space, working at height, and electrical isolation. You can add more later.
2. Choose your format. Paper books from safety suppliers, Word/PDF templates, or a digital tool.
3. Define who can authorise. Not everyone should be able to sign off a permit. Authorisers need to understand the hazards and the precautions.
4. Brief your team. Everyone needs to know that a permit is required before these tasks start, and that starting work without one is a serious issue.
5. Audit regularly. Check that permits are being completed properly. Look for patterns — are checklists being ticked without the checks actually being done?

The legal position

There is no single law in the UK that says "you must use permits." Instead, permits are one way to demonstrate compliance with several regulations:

• Management of Health and Safety at Work Regulations 1999 — requirement for suitable and sufficient risk management
• Confined Spaces Regulations 1997 — requirement for a safe system of work
• Electricity at Work Regulations 1989 — requirement for safe isolation
• Construction (Design and Management) Regulations 2015 — requirement for managing high-risk work
• Regulatory Reform (Fire Safety) Order 2005 — controls on hot work in buildings

HSE guidance document HSG250, "Guidance on permit-to-work systems," is the standard reference. It is well worth reading if you are setting up a system.

Summary

A permit-to-work system is a formal way to control high-risk tasks on site. It is not bureaucracy for its own sake — it is a structured check that catches the things people forget when they are in a hurry. For small contractors, the challenge has always been finding a system that is practical and affordable. Paper works but has real limitations. Digital tools are now accessible at price points that make sense for SMEs.

The important thing is to have a system that your team actually uses, not one that sits in a drawer.