There’s no fixed legal ratio for fire marshals in UK law. The number you need depends on the level of fire risk in the workplace, the size and layout of the building, the number of staff and visitors on site at any given time, and how shift patterns affect coverage. The fire risk assessment is what ultimately decides it.

Headcount ratios alone cannot establish adequate coverage. Start with the emergency duties, the time and assistance they require, and the competent people actually available on each shift.

What the law actually says

In England and Wales, the Fire Safety Order requires appropriate fire-safety arrangements and enough competent people for the relevant tasks, considering the premises’ size, risks and distribution of hazards. Scotland and Northern Ireland have separate fire-safety laws.

The Order doesn’t fix a number of marshals. It tells you the outcome it wants — adequate fire safety, prompt and effective evacuation, competent people in place — and leaves you to work out the staffing that achieves that outcome.

The mechanism that turns the outcome into a number is the fire risk assessment. A proper assessment looks at the building, the activities carried out in it, who’s likely to be present, and what could go wrong, then specifies the arrangements needed — including how many trained fire marshals or fire wardens. Without an assessment, any number you pick is essentially guesswork.

This is why two workplaces of the same size can legitimately need very different numbers of marshals. A 50-person open-plan office on the ground floor of a modern building isn’t the same risk as a 50-person upholstery workshop with foam stocks and electric saws. The Order treats them differently because the assessments will.

Why a ratio cannot decide the number

Assess the tasks and coverage in different types of premises:

  • Simpler premises — assess the exits, occupants and emergency duties; a low headcount does not remove the need for workable arrangements
  • More complex premises — consider separate areas, visitors, equipment and how duties can be carried out at the same time
  • Higher-risk premises — allow for the assistance, specialist arrangements and staffing needed for safe evacuation

Ratios such as one person per 50, 20 or 15 employees are not statutory requirements or a verified HSE staffing formula. They cannot demonstrate that a particular workplace has enough trained people.

What “low”, “medium” and “high” risk actually mean

Risk assessments consider the nature of the hazards and the people exposed. Two useful questions are:

  • Likelihood: how probable is it that a fire starts? This depends on the materials present, the activities carried out, the electrical load, the number and habits of occupants.
  • Severity: if a fire did start, how bad could it get? This depends on the fuel load (how much there is to burn), the layout (how easily it spreads), and how easily the occupants can leave (how many, how mobile, how complex the escape routes).

A small modern office with sprinklers, low fuel load, mobile occupants and short clear escape routes is at the low-risk end. A care home with vulnerable residents who can’t self-evacuate, or a warehouse storing flammable goods on high racks, sits at the high-risk end. Most workplaces sit somewhere in between.

An assessment must identify the actual precautions and arrangements needed. A simple low/medium/high label, with or without a staffing ratio, is not enough.

Building factors that change the number

Even within a risk band, certain features push the number up:

  • Multiple floors. Check that the evacuation duties on each occupied floor can be performed safely and promptly; one person per floor is not a universal legal formula.
  • Multiple buildings or wings. Assess whether duties can be covered concurrently across the occupied areas.
  • Multiple assembly points. Allocate appropriate reporting and coordination arrangements for each point used.
  • Public-facing areas. Restaurants, shops, leisure venues need marshals proportional to peak occupancy, not staff headcount, because customers also need directing.
  • Vulnerable occupants. Care homes, hospitals, schools with younger children — these need higher densities because evacuation takes longer and needs more help.
  • Shift patterns. Each shift needs its own marshal coverage. If you operate 24/7, you can’t have only day-shift marshals.

Cover for absence

The number you appoint isn’t the number on duty. It’s the number on duty plus enough cover for holidays, sickness, training and other planned absences.

Plan absence cover from actual rotas, leave, sickness and training. Doubling a minimum is not a statutory rule and may still leave gaps; verify that the required duties remain covered whenever the premises are occupied.

A common failure mode is appointing exactly the minimum and then losing coverage every time someone takes annual leave. The fire and rescue service’s audit is no kinder on a Tuesday in August when half your marshals are on holiday than it is in March when they’re all back.

Deputy marshals need the same training as primary marshals. There’s no shortcut where you can have one fully-trained person and a couple of “informal” backups. Either someone is competent for the role or they aren’t.

Worked examples

A small office (30 staff, low risk)

A 30-person office on a single floor, in a modern building with clear short escape routes, low fuel load, and no special hazards. The risk level is low.

An assessment might find that one person can perform the assigned duties on this shift, with trained cover when absent. That is an illustrative planning outcome, not a one-per-50 minimum or a recommendation for every 30-person office.

A busy restaurant (38 staff across two shifts, plus 40 customers, medium risk)

Consider a restaurant with 38 staff employed across kitchen and front-of-house shifts and space for 40 customers. Establish how many staff are present at each time, where they work and what assistance customers may need.

The staffing requirement cannot be calculated from these totals alone. Assess concurrent occupancy, kitchen hazards, exits, customer assistance and shift handovers, then check the rota against the duties. There is no official basis here for prescribing 12 to 14 marshals.

A multi-floor warehouse (50 staff across three shifts, high risk)

Consider a warehouse employing 50 people across three shifts, with high-rack storage and some flammable goods. Establish the actual occupancy and activities on each shift.

Do not multiply all 50 employees by a ratio and then by three shifts. Identify the duties and occupied areas on each shift, safe travel routes and absence cover. The assessment may require different staffing on different shifts.

A 12-person creative agency (single floor, low risk)

A small creative agency with twelve staff in an open-plan office on the second floor of a serviced office building. Low risk.

Agree the tenant’s and building management’s duties, then check who is available to carry them out during occupancy and absences. One appointed person plus a deputy may be one arrangement, but the headcount alone cannot establish that it is sufficient.

What happens if you don’t have enough

The Fire Safety Order is enforced by the local fire and rescue service through audits of non-domestic premises. Where they find inadequate arrangements, they can issue:

  • Informal advice notices — guidance to fix specific issues, no formal sanction
  • Formal enforcement notices — legally binding, with deadlines for compliance
  • Prohibition notices — preventing use of all or part of the premises until specific risks are addressed
  • Prosecution — for serious or persistent breaches, with unlimited fines and (in extreme cases) custodial sentences

Enforcement depends on the failings and the risk to people, not a national marshal quota. Inadequate staffing, training or evacuation arrangements can require corrective action even where a business has appointed people with marshal titles.

Keep evidence of the assessed duties, competent people, coverage and drills. A nominal headcount or certificate list does not by itself establish that the emergency arrangements work.

Common questions

Is having a fire marshal a legal requirement?

The Fire Safety Order does not prescribe that job title. It requires suitable arrangements and sufficient competent assistance for the relevant duties; what that means depends on the premises and activities.

What if the fire risk assessment specifies a different number?

Follow a suitable and sufficient assessment of the actual duties and risks. A ratio is not a legal staffing rule, and an assessment should be revisited if the resulting coverage does not work in practice.

Can the responsible person be the fire marshal too?

Yes, in small workplaces this is common. A two-person business often has both partners trained as fire marshals. The roles are conceptually distinct (one is the legal duty-holder, the other is the operational role), but nothing prevents the same person filling both.

Do contractors and visitors count towards the number we need?

The risk assessment should account for them. If you regularly have non-staff in the building — customers, contractors, students, patients — your marshal count needs to reflect peak total occupancy, not just employee headcount.

What about hybrid working — fewer people in the office on any given day?

Plan coverage for actual occupancy, including peak attendance and shifts. Check that the trained people relied on in the emergency plan will be present; remote staff cannot cover on-site duties.

Once you’ve worked out the right number, the next step is getting them trained. Our Fire Warden Training course covers the full role at £18 per learner — RoSPA approved, CPD accredited, 60 to 90 minutes online, with an instant certificate on completion. Bulk discounts kick in at 10 delegates (10% off), 50 delegates (20% off), 100 delegates (30% off) and 500 delegates (40% off), so larger workplaces save substantially when training a whole team.

For more on what the role actually involves once they’re trained, see the fire marshal responsibilities page. And if you’re trying to decide what to call the role internally, the fire marshal vs fire warden page covers that question.

Sources & references

Official guidance checked on 15 October 2026. Requirements vary by UK nation and premises.

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Mark McShane
Mark McShane
Health & Safety Training Specialist, Online CPD Academy

Mark writes about workplace health & safety, fire warden duties and accredited online training for Fire Warden Training, part of Online CPD Academy.