Fire safety on construction sites: risk assessment, hot works, and escape routes

The legal framework

Fire safety on construction sites is governed by several overlapping pieces of legislation:

• Regulatory Reform (Fire Safety) Order 2005 (FSO): The primary fire safety legislation for England and Wales. It applies to all workplaces, including construction sites. Scotland has equivalent legislation under the Fire (Scotland) Act 2005.
• CDM 2015: Requires the principal contractor to include fire prevention and emergency procedures in the construction phase plan.
• Health and Safety at Work Act 1974: The general duty to ensure health and safety includes protection from fire.

Under the FSO, the "responsible person" must carry out a fire risk assessment, implement appropriate fire precautions, and keep the assessment under review. On a construction site, the responsible person is usually the principal contractor. On single-contractor projects, it is the contractor.

Joint Fire Prevention Committee guidance document "Fire Prevention on Construction Sites" (often called the Joint Code of Practice or JCoP) is the industry standard reference. It is regularly updated and is referenced by insurers, fire services, and HSE.

Fire risk assessment for construction sites

A fire risk assessment for a construction site differs from one for a finished building because the site changes constantly. The assessment must be dynamic and reviewed as the project progresses. The process follows five steps:

1. Identify fire hazards: Sources of ignition (hot works, electrical faults, smoking, arson), fuel sources (timber, insulation, solvents, gas cylinders, waste), and oxygen sources (natural ventilation, compressed air).
2. Identify who is at risk: All workers on site, particularly those working in confined spaces, at height, or in areas with limited escape routes. Visitors, members of the public near the site boundary, and occupants of adjacent buildings.
3. Evaluate the risks: Consider the likelihood of a fire starting and the consequences if it does. A site with extensive timber frame construction, incomplete fire stopping, and multiple hot works activities has a very different risk profile from a concrete frame site.
4. Implement controls: Measures to prevent fire (material storage, hot works procedures, electrical safety), measures to detect fire (fire watch, smoke detection in enclosed spaces), and measures to protect people if fire occurs (escape routes, alarms, extinguishers, muster procedures).
5. Record, review, and update: The assessment must be documented. It must be reviewed whenever the site layout changes significantly, when new fire risks are introduced, or after any fire incident or near miss.

On a project lasting 18 months, the fire risk assessment at month one (site clearance and foundations) will be very different from the assessment at month twelve (internal fit-out with extensive flammable materials and incomplete fire compartmentation). Regular review is not optional.

Hot works permits

Hot works are the single largest cause of construction site fires. Hot works include welding, oxy-fuel cutting, brazing, soldering, grinding, and any other activity that generates heat, sparks, or naked flames.

A robust hot works permit system requires:

• Written permit: Issued by a competent person (typically the site manager or fire marshal) before any hot works begin. The permit specifies the location, the work to be carried out, the duration, and the precautions required.
• Area preparation: Flammable materials must be removed from the work area and for a minimum radius of 10 metres (or as specified in the fire risk assessment). If removal is not possible, fire-resistant blankets or screens must be used.
• Fire watch: A dedicated person with appropriate extinguishing equipment must be present during hot works and for at least 60 minutes after the work is completed. The fire watch checks for smouldering materials that could ignite after the work stops.
• Extinguishing equipment: Appropriate fire extinguishers must be immediately available at the point of work. The type and quantity depend on the work and the surrounding materials.
• Permit closure: The fire watch must confirm that the area is safe before the permit is closed. The permit record should include the start time, end time, fire watch duration, and the signature of the fire watch.

Paper-based hot works permits are common but have limitations. They can be lost, backdated, or issued without proper checks. Digital permit systems create a timestamped, auditable record that is harder to circumvent and easier to review.

Escape routes and muster points

Escape routes on construction sites must be planned, maintained, and communicated to all workers. The challenges specific to construction include:

• Changing layout: As the building takes shape, escape routes change. Stairs that were accessible last week may be blocked by formwork this week. Routes must be reviewed and updated continuously.
• Incomplete stairways: Until permanent stairs are installed, temporary stairs, ladders, or hoists serve as escape routes. These must be maintained and clearly signed.
• Multiple levels: Workers at height need escape routes that do not require them to pass through fire-affected areas. On multi-storey structures, this may mean providing escape from every level to at least two stairways.
• Signage and lighting: Escape route signage must be in place and visible, even when power is lost. Battery-backed emergency lighting should be provided in enclosed areas.

The muster point must be a safe distance from the building and from any material storage or fuel compounds that could become involved in a fire. The location should be included in the site induction and clearly marked on site.

Knowing who is on site at the time of an emergency is critical for muster. Paper sign-in sheets are unreliable: workers forget to sign out, sheets get lost, and counting heads against a paper list in an emergency is slow. Digital muster systems that provide a real-time list of everyone on site make the roll call faster and more accurate. AttendIQ provides real-time attendance data so fire marshals know exactly who to account for.

Fire points and extinguishers

Fire points should be established at regular intervals across the site. Each fire point typically includes:

• At least two fire extinguishers appropriate to the fire risks in the area (water, foam, CO2, or dry powder depending on the materials and equipment nearby).
• A fire alarm call point or air horn if the site does not have a wired alarm system.
• A fire action notice showing what to do if you discover a fire.
• Clear signage identifying the fire point location.

HSE and the JCoP recommend that no worker should have to travel more than 30 metres to reach a fire extinguisher. On large sites, this means fire points on every floor and in every work area. Fire extinguishers must be inspected monthly and serviced annually by a competent person.

As the site develops, fire points need to move. What was an appropriate location during the groundworks phase may be inaccessible during the superstructure phase. The site fire plan (part of the fire risk assessment) should be updated with fire point locations at each phase.

Training and fire drills

Every worker on site must receive fire safety training as part of their induction. The training should cover:

• How to raise the alarm (where call points are, the alarm signal, who to notify).
• The escape routes from their work area.
• The muster point location and roll call procedure.
• Where fire extinguishers are and how to use them (for those designated as first responders).
• The hot works permit process and why it matters.
• Housekeeping: why waste accumulation, blocked escape routes, and improper material storage are fire risks.

Fire drills should be carried out regularly. Monthly drills are good practice on construction sites, and a drill should be held whenever there is a major change in site layout, workforce, or fire risk. The drill tests whether the alarm can be heard across the site, whether workers know the escape routes, and whether the muster process produces an accurate headcount.

Fire safety awareness should be built into your site induction so that every worker who arrives on site knows the fire procedures from day one. AttendIQ's digital induction system ensures that fire safety content is delivered to every worker and that completion is recorded against their profile.