How many fire marshals do you need? UK requirements explained

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.

That said, most UK fire safety professionals work to a well-established rule of thumb based on workplace risk level. We'll cover the legal framework first, then the ratios, then walk through a few worked examples.

What the law actually says

The Regulatory Reform (Fire Safety) Order 2005 requires the responsible person — usually the employer — to "make and give effect to such arrangements as are appropriate" for managing fire safety. The standard the Order uses is "suitable and sufficient": the arrangements must match the risk.

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.

The ratio rule of thumb

For most businesses, the conventions used across UK fire safety training and consultancy are:

• Low-risk premises — one fire marshal per 50 employees
• Medium-risk (or "normal") premises — one per 20
• High-risk premises — one per 15

These ratios aren't from the legislation. They've evolved through guidance from training providers, fire safety consultancies and the Health and Safety Executive, and they've stuck because they tend to produce sensible numbers in practice. Treat them as a starting point for the fire risk assessment, not an answer that lets you skip the assessment.

What "low", "medium" and "high" risk actually mean

There's no legal definition of these bands either, but the working approach is to consider two factors:

• 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.

If you're uncertain about your risk level, your fire risk assessment will have classified the premises (or should have). If it hasn't, that's a more pressing issue than the marshal headcount.

Building factors that change the number

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

• Multiple floors. A common rule of thumb is at least one fire marshal per floor, regardless of headcount. A small two-person workshop on a separate mezzanine still needs cover.
• Multiple buildings or wings. Each needs its own coverage if it has a separate exit set.
• Multiple assembly points. If your evacuation procedure brings staff to different external points, you need a marshal at each.
• 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.

A reasonable working principle: aim for at least double the minimum number of marshals you need on duty at any one time, scaled up for high-risk environments. So a small office that needs one marshal on duty might appoint two; a 100-person low-risk site that needs two on duty might appoint four; a large warehouse that needs five on duty across shifts might appoint ten.

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.

Applying the 1:50 ratio gives a minimum of one fire marshal. Add cover for absence and shift changes, and the practical number is two — both fully trained, with overlapping working hours so there's always at least one on site during normal operating hours.

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

A restaurant with a kitchen of 30 staff working three shifts and a dining area with 8 staff working two shifts, peak customer occupancy of 40. Kitchens are medium-to-high risk because of cooking equipment and oils; the front of house is medium-risk because of public occupancy.

The headcount calculation here gets more involved. You need cover across all three kitchen shifts, two front-of-house shifts, and at peak times you've got around 80 people in the building (38 staff plus 40 customers). Most fire risk assessments would specify around 12 to 14 trained marshals to give safe coverage on every shift with adequate redundancy. That seems high until you remember that on a Saturday evening you may have a maximum-occupancy dining room with three shift handovers happening — and someone has to be running fire safety on every one of them.

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

A warehouse with 50 staff working in three rotating shifts, with high-rack storage including some flammable goods. High risk.

Applying the 1:15 ratio gives roughly four marshals per shift. Three shifts means at minimum twelve trained marshals, and with cover for holidays and sickness the realistic number is around fifteen. If the warehouse has multiple floors or multiple buildings sharing one site, you'd need to add per-floor or per-building coverage on top.

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.

The minimum here is one fire marshal — but with twelve people, that means you need a deputy too, otherwise the agency has no fire safety arrangement on any day the primary marshal isn't in. Two trained staff is the practical answer. Several of them might also rely on the building's broader fire safety arrangements (the building's overall responsible person, multi-tenant alarm system, etc.) — but the agency itself still needs its own trained people for sweep duties on its floor.

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

Recent MHCLG figures show formal enforcement notices have been at their highest levels since the early 2010s, with a substantial year-on-year increase in fire safety prosecutions. Inadequate fire marshal arrangements aren't typically the sole reason for a prosecution, but they do show up in the chain of failings.

The pragmatic point: in an audit, what regulators want to see is a current fire risk assessment, a sensible number of trained marshals appointed, evidence that they're actually doing their checks (the log book), and an emergency plan that everyone knows. If those are in place, the marshal count rarely becomes an issue. If they aren't, the count is one of several things that gets flagged.

Common questions

Is having a fire marshal a legal requirement?

Not by name, but in effect yes. The Fire Safety Order requires the responsible person to appoint enough competent persons to carry out the preventative and protective measures the fire risk assessment specifies. For almost every workplace, that means appointing fire marshals.

What if the fire risk assessment specifies a different number?

Follow the assessment. The 1:50 / 1:20 / 1:15 ratios are a starting heuristic. If a properly conducted risk assessment specifies more (or fewer) marshals for your specific circumstances, that's the binding number.

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?

The fire risk assessment should reflect actual working patterns. If half your workforce is remote on a typical Wednesday but full attendance happens monthly, you need cover for the high days, not just the average. Many hybrid workplaces have over-rotated towards skeleton staffing and ended up with no qualified marshal on site some days.

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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.