What information do I need to estimate occupancy?

You need the clear width of the relevant escape route in millimetres, the travel distance in metres, the overall risk level and whether escape is in one direction or more than one direction.

Why does travel distance matter?

Travel distance affects whether people can reach a place of reasonable safety in time. It should be checked alongside exit width, number of escape routes, risk level, occupancy type and management controls.

Building Occupancy Calculator

Q: Can this calculator replace a fire risk assessment?

No. The calculator is an indicative tool for escape route capacity and travel distance checks. A suitable and sufficient fire risk assessment should consider the actual premises, occupancy, management arrangements, fire precautions and people at risk.

Estimate maximum occupancy from escape route width, overall fire risk and travel distance. Use it as a practical starting point for UK premises, then confirm the result within a suitable and sufficient fire risk assessment.

Last reviewed: July 2026

Calculate Escape Route Capacity

This tool uses the common escape route capacity figures from HM Government fire safety risk assessment guidance. It is not a design certificate and should not be used in isolation for complex, high-risk, licensed, sleeping, healthcare, care, assembly or multi-storey premises.

Important: Where there is more than one escape route, a fire risk assessment may need to discount the largest exit if it could be affected by fire. Travel distance, door direction, escape route condition, fire doors, alarm provision, emergency lighting and people needing assistance still need competent review.

Select Overall Fire Risk

Choose the risk level that best reflects the area being assessed. If unsure, use the more cautious option and seek competent advice.

High

Use higher risk where a fire could start, grow or affect escape routes quickly, or where people may move slowly or need assistance. This may include higher fuel loads, flammable materials, process risks, hidden voids, vulnerable occupants or weak warning arrangements.

Normal

Use normal risk where the premises does not clearly fall into higher or lower risk. Many ordinary commercial premises sit here, but the category may change if occupants need assistance, escape routes are compromised or fire could develop quickly.

Low

Use lower risk only where occupancy is low, occupants are familiar and able to escape unaided, ignition likelihood is low, fuel load is limited, fire spread is unlikely and warning would be prompt.

Escape route basis

Use single direction where the initial travel is in one direction only, such as a dead end or inner room route.

Area layout

Seating in rows can reduce suggested travel distances compared with more open layouts.

Enter Escape Route Information

Enter the narrowest clear unobstructed width people can pass through, plus the approximate travel distance to the nearest final exit, storey exit, protected stairway or place of reasonable safety.

Location within the premises

Width in mm

Travel distance in m

Maximum occupancy

Distance result

Occupancy Calculator Result

Location within the premises	Width in mm	Travel distance in m	Maximum occupancy	Distance result

How To Use The Result

Treat the result as an indicative escape capacity calculation, not a final approval of occupancy.
Check whether the largest exit should be discounted because it could be affected by fire.
Confirm travel distances by walking the actual route around furniture, storage, racking, counters or seating layouts.
Review escape route width alongside fire alarm provision, emergency lighting, fire doors, signage, management procedures and people who may need help to evacuate.

Need A Fire Risk Assessment?

If you are setting occupancy limits, changing a layout, licensing a venue or reviewing escape routes, a competent assessor can confirm whether the premises is suitable for the intended use.

Request a fire risk assessment quote

Common Questions

Can this calculator replace a fire risk assessment?

No. It is an indicative calculation tool. A fire risk assessment should consider the actual building, occupancy, hazards, escape routes, fire precautions and management arrangements.

Why does the tool ask for travel distance?

Exit width is only one part of escape safety. Travel distance affects how quickly people can reach a final exit, storey exit, protected stairway or place of reasonable safety.

What if the travel distance warning shows a problem?

Review the layout, reduce occupancy, improve escape arrangements or seek competent advice. Do not rely on the occupancy number alone if travel distance appears unsuitable.