BS 7273-4: Actuation of Release Mechanisms for Doors

Overview

BS 7273-4:2015 + A2:2023 is the British Standard that governs how electrically locked or held-open doors on escape routes must be released in the event of fire or system fault.

The standard ensures that escape doors controlled by electricity always release reliably, quickly, and fail-safe, maintaining the principle of free egress under the Regulatory Reform (Fire Safety) Order 2005 and related legislation.

Scope

BS 7273-4 applies to:

• Electrically locked doors (maglocks, solenoid bolts, shear locks, etc.)
• Electrically held-open doors (e.g. electromagnetic door retainers)
• Doors on escape routes or final exits where release must be guaranteed

It does not apply to purely mechanical hardware (e.g. un-locked panic bars).

Categories of Actuation

BS 7273-4 defines three categories of system integrity, depending on the criticality of the door:

Manual Release Devices

Every electrically locked escape door must also have a local manual means of release, even if the fire alarm system is interfaced.

Acceptable Devices

• BS EN 54-11 Type B manual call point (MCP)

  • Resettable or frangible “break glass” type
  • Provides direct contacts to drop lock power

• Emergency Door Release (EDR) unit to BS 7273-4 requirements

  • Clearly marked green unit labelled Emergency Door Release
  • Provides sustained fail-safe release

Placement

• Adjacent to the door on the escape side
• Height approx. 1.4 m, visible and unobstructed
• Illuminated where lighting is poor

Non-Compliant Devices

• Timed auto-reset units (that re-lock after a delay)
• Push-and-hold-only buttons (release only while held in) Both fail because the standard requires sustained release until reset.

Performance & Timings

• Door must release within 3 seconds of actuation (fire, fault, or manual).
• Release devices must be robust and suitable for repeated operation.
• Locks must fail safe (loss of power releases the door).

Integration with Fire Alarm Systems

• Release mechanisms must be controlled by the fire detection and alarm system (FDAS).
• Fire alarm interface alone is not sufficient — local MCP/EDR still required.
• Categories A and B require fault monitoring of circuits.

Panic Bars and Exit Hardware

BS EN 1125 (panic bars) and BS EN 179 (emergency push pads/levers) require that doors open by a single mechanical action, regardless of electrical systems.

Non-Compliant

• Maglocks fitted to doors with panic bars or pads:

  • The panic hardware cannot mechanically override the lock.
  • Escape depends on electrical release, breaching EN 1125/179.

Compliant

• Electrified panic hardware tested and CE-marked to EN 1125/179:

  • Push bar always mechanically releases the door.
  • Electronic control is supplementary (e.g. latch retraction for access).

• Mechanical escape doors kept separate from access-controlled doors.

Maintenance

• All doors, release devices, and interfaces must be tested during routine FDAS maintenance (BS 5839-1).

• MCP/EDR units should be checked regularly for correct operation.

• Documentation must record:

  • Category of actuation per door
  • Wiring and interfaces
  • Commissioning/test results

Key Points

• BS 7273-4 ensures electrically controlled escape doors always release fail-safe.
• Manual local release (green MCP/EDR) is always required.
• Auto-reset or push-and-hold devices are non-compliant.
• Panic bars must provide a mechanical override — maglocks across them are not acceptable.
• Compliance requires correct design, installation, testing, and maintenance.