Short answer. The Regulatory Reform (Fire Safety) Order 2005 requires fire doors to be kept in efficient working order, but the specific tolerances people check against, gap widths, hinge numbers, glazing type, come from BS 8214:2016 and the individual door's certification, not from the Order itself. Residential buildings over 11 metres have additional statutory check frequencies under the Fire Safety (England) Regulations 2022.
A fire door has one job: to contain fire and smoke for a specified period. A standard FD30 fire door provides 30 minutes of fire resistance, an FD60 provides 60 minutes. During that time the door holds back flames, heat and smoke, keeping escape routes clear and giving occupants time to get out.
Without fire doors, a fire that starts in one room can spread through a building within minutes, and smoke can fill corridors and stairwells almost as fast. A fire door only delivers that protection if it is correctly installed, properly maintained, and kept closed.
Article 17 of the Regulatory Reform (Fire Safety) Order 2005 requires the responsible person to ensure that fire safety measures, fire doors included, are subject to a suitable system of maintenance and are maintained in efficient working order and in efficient working condition. The Order does not itself specify gap widths, hinge counts or glazing types.
Those specifics come from BS 8214:2016 (the code of practice for fire door assemblies) and from the certification of the individual door set, which is what a fire door needs to comply with to remain "as tested". A door's certificate, where one exists, takes precedence over general guidance for that specific door.
Under BS 8214 and typical door certification: gaps at the head and jambs are usually around 3mm when the door is closed. The threshold (bottom) gap is different: where the door has no smoke seal, a larger gap of roughly 8 to 10mm can be acceptable; where a smoke seal is fitted, the gap needs to be smaller, generally in line with the door's certificate. Intumescent strips and smoke seals must be intact and unobstructed, glazing must be fire-rated to the door's specification, and hinges must match what the certificate requires, commonly three hinges for a standard FD30 door.
Signage is covered by BS 5499 for fire door signs such as "Fire door keep shut", and a certified door should carry a permanent marking, typically a BWF-Certifire or BM TRADA plug or label, confirming its rating and that it has not been substituted.
The Fire Safety (England) Regulations 2022 added specific check frequencies for multi-occupied residential buildings over 11 metres in height: responsible persons must arrange quarterly checks of fire doors (including self-closing devices) in communal areas, and use best endeavours to carry out annual checks of flat entrance doors. These duties sit alongside, not instead of, the general FSO article 17 maintenance duty, and they do not apply to buildings under that height threshold.
A basic fire door check does not need specialist equipment. Walk up to each fire door and check the following:
Some issues, adjusting a closer, replacing a missing seal, are quick fixes. Others, a damaged door or incorrect glazing, need a fire door specialist.
Fire doors are part of a wider compartmentation strategy: walls, floors, ceilings and doors work together to divide a building into fire-resistant sections. If any element fails, the strategy is compromised. A fire risk assessment includes a visual, sampled check of fire doors as part of the wider assessment, alongside escape routes, detection and management arrangements, though it is not a substitute for a full engineering survey of every door where one is needed.
Guidance on maintaining fire doors and other fire precautions in efficient working order is set out in the Regulatory Reform (Fire Safety) Order 2005, available from legislation.gov.uk.