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Somewhere on your fire safety certificate is a number: the maximum number of people your venue may legally hold. Almost no owner knows how that number is actually built — and that matters, because it decides both how much revenue you can put on the floor and whether you're inside the law on a packed Saturday.
There is no single European fire-safety code. Every member state — often every municipality — sets its own rules, and yours depends on the local fire authority that signs off your operating licence. What repeats everywhere is the same underlying logic: how much floor area one guest needs, how much exit width a crowd needs to leave the building, and how far someone may walk before that exit stops counting as safe.
Nobody writes that logic out for a restaurant owner. It sits inside a standard an architect or fire-safety consultant reaches for, and the result — the number on the certificate — lands on your desk with none of the arithmetic behind it. That's why almost nobody can check it themselves, let alone use it to make a decision about the floor plan.
This article walks through the four numbers that build that figure: floor area per guest (which changes by zone), exit width per person, travel distance to the nearest exit, and — the number nobody calculates — the gap between your legal capacity and the covers you're actually putting on the floor today.
Why this cuts both ways
Most venues sit well under their legal capacity. A room designed for 90 guests that only seats 68 because of an awkward table layout is leaving 22 covers on the table on a fully booked night — revenue the law would allow, that simply isn't there. Almost nobody calculates that gap, because almost nobody knows the number on the other side of it.
A smaller number of venues sit right at the limit, or over it — usually after a renovation added tables without revisiting the exits. That's not a fine you feel on a quiet Tuesday: it's a problem that only shows up at an inspection, or worse, during an evacuation the exit can't actually clear fast enough. Both sides of that gap deserve a number, not a guess.
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Each one feeds the next. Change the layout and the first number moves, and all three after it move with it.
1. Floor area per guest — and it changes by zone
Every occupancy calculation starts with one factor: how many square metres does a single guest need? The answer depends entirely on what that zone is doing. A seated dining area with fixed tables and chairs needs by far the most room per person — guests are spread out, chairs push back, and a server has to move between them. A standing bar area needs less than a third of that: people stand closer together and there's no chair taking up floor. A waiting or lounge area sits somewhere in between.
Widely used design values are roughly 1.5 m² per guest for seated dining with tables and chairs, 0.5 m² for a standing bar, and 0.65 m² for a waiting area with loose seating. Using one blanket figure for the whole room is the single most common mistake: it either overstates what a dining room can hold, or understates what a bar can. Calculate per zone, then add the results together.
The same 20 m², fitted out three ways — the number of guests it holds differs by nearly a factor of three.
The standing bar fits almost three times as many guests into the same area as the dining room. Using one blanket factor for the whole room always overstates one zone or understates the other.
2. Occupant load decides how much exit width you need
Once you know how many people a zone is legally allowed to hold — the occupant load — that decides how much clear width your exits need combined. A widely used rule of thumb is roughly 5 mm of clear exit width per person, with a minimum of about 800 mm for a single door leaf (the minimum width to let someone using a wheelchair or walker through). At 60 guests that works out to roughly 800 mm — one wide door is still just enough. At 150 guests the calculation alone climbs to 750 mm, and most codes require a second, separately located exit past a certain occupant load regardless of what the width arithmetic says.
That threshold sits around 60 people in practice, though the exact figure varies by country and building type. Above it, width alone stops being the whole story: one exit that jams under panic is a risk no calculation can offset, no matter how wide that single door is.
Required exit width climbs in direct proportion to occupant load — until the point where a second exit becomes mandatory outright.
2nd exit required
2nd exit required
2nd exit required
2nd exit required
Past the red bars, one exit no longer suffices regardless of how wide that single door is — a second, separately located exit becomes the rule.
3. Travel distance is the second, independent trigger for a second exit
Occupant load isn't the only reason to require a second exit. How far a guest has to walk to reach an exit counts too, independently of how many people are in the room. A widely used limit is roughly 30 metres in a building without sprinklers, and about 45 metres in one that is sprinklered — the sprinkler buys time, and that time buys extra metres of travel distance.
That means a long, narrow venue with only 40 guests can still need a second exit, purely because the furthest table sits too far from the door — while a compact room with 55 guests can get by on one exit. The two triggers, occupant load and travel distance, work independently: you need a second exit the moment you cross EITHER limit, not only once you cross both.
4. Your legal capacity against your actual covers
The first three numbers give you one figure: the maximum occupant load your room can legally hold. Compare that to the covers you're actually putting on the floor today, and you get the number that appears on no certificate but decides more than any of the others whether this article was worth reading: the gap.
A positive gap is revenue sitting on the table — your room could legally hold more guests than your current layout allows. A negative gap isn't a fine on a quiet night, it's a risk waiting for the next inspection or, worst case, the moment you can no longer afford it: an evacuation. Both deserve a number, and the calculator below gives you that number for your own layout.
Run the numbers on your own venue
Enter the area of each zone, whether your building is sprinklered, the combined width of your exits and the travel distance to the nearest one, and the covers you're actually putting on the floor today. The calculator applies the same four steps above to your own figures.
Occupancy & egress calculator
Planning figures, not a substitute for your fire inspection — see the FAQ below.
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These are widely used design figures for planning, not a fixed legal text. Exact standards vary by country, municipality and building type. Always have the final figures confirmed by the fire authority or fire-safety consultant who signs off your operating licence.
A negative gap doesn't automatically mean you need to shrink — often it's fixed by revisiting the layout, opening a second exit that already exists but isn't marked as one, or clearing an obstacle in front of the door. A positive gap means a simple reshuffle of tables could bring your legally allowed revenue closer, without adding a single square metre.
What to do about it today
You don't need to wait for the next inspection to work this out. Two scenarios, and what each actually asks of you:
If your gap is positive (room to spare)
- Re-measure your current room against the three zones and compare it to your existing table plan — the room is often lost to an inefficient walking route, not a lack of square metres.
- Consider a few extra standing tables at the bar instead of seated ones — that zone absorbs by far the least extra room per additional guest.
- Discuss the extra capacity with your fire-safety consultant before you add tables — amending an approved plan can be a short formality, not a new procedure.
If your gap is negative (over the limit)
- Check first that every existing emergency exit is marked as one and clear of obstacles — that sometimes solves the whole problem without moving a single table.
- Measure the travel distance to your nearest exit from the furthest table; if it exceeds the limit, a second exit is the more likely fix, not a wider door.
- Request a re-inspection as soon as the layout is corrected — a certificate describing an old table arrangement won't protect you at an inspection of the current one.
The number you can now check yourself
The figure on your fire safety certificate isn't an inspector's arbitrary call — it's the sum of four steps you can now check yourself: area per zone, exit width per person, travel distance to the exit, and the gap with your actual covers. That last number is the one nobody calculates for you, and it's exactly the one that decides whether you're leaving revenue on the table today or carrying a risk tomorrow.
Use the calculator above as the start of a conversation with your fire-safety consultant, not a replacement for one — the exact standards vary by country and building, but the four steps behind them are the same everywhere.