After years in the industry we still get questions about when to use fail safe vs fail secure electric strikes. Electrical inspectors in Massachusetts and New Hampshire gave us their input on this topic over few occasions. The terms fail safe and fail secure describe how an electrified lock responds during a power loss: fail safe locks unlock (prioritizing safety & egress), while fail secure locks remain locked (prioritizing security).
How Each Type Works
· Fail Safe: Requires power to stay locked; without power, the door automatically unlocks. Common in doors where rapid evacuation is critical, such as emergency exits and fire rated stairwells.
· Fail Secure: Requires power to unlock; without power, the door remains locked from the outside but can typically be opened from the inside for egress or with a mechanical override. Suited to perimeter doors or rooms holding valuable assets that require persistent security.
Use Fail Safe for:
o Stairwell doors that require re-entry in an emergency
o Doors in healthcare or high-traffic areas where life safety is a top concern
o Interior access-controlled doors mandated by code to unlock during fire alarms or power loss
Use Fail Secure for:
o Entry points where persistent security is paramount, such as server rooms, employee entrances, and fire-rated perimeter doors.
o Fire-rated doors, where local regulations (e.g., NFPA 80) often require fail secure strikes for positive latching.
Regulatory and Safety Considerations
· Building codes often dictate which type must be used based on door location and fire safety standards.
For example, many codes stipulate fail safe for reentry doors and fail secure for exterior/fire rated doors.
· Electromagnetic locks are generally only available as fail safe, while electric strikes can be manufactured as either.
· Regardless of fail mode, most locks allow for interior egress via a mechanical or electronic release method, maintaining compliance with life safety codes.
Power and Maintenance Issues
· Fail Safe locks require a constant power source to stay locked, potentially driving up energy costs or necessitating battery backup systems.
· Fail Secure locks only need power when unlocking, leading to lower overall energy consumption and enhanced security during outages.
Common Misconceptions
· Not all types of electric strikes and locks are available in both fail safe and fail secure versions; selection should match application needs and door codes.
· The use of mechanical override keys in fail secure systems does not inherently compromise security if access to keys is managed responsibly.
Final Thoughts
Selecting between fail safe and fail secure electric strikes is a balance between safety and security, informed by occupancy needs, door type, regulatory requirements, and power availability. Understanding these distinctions is vital for compliance, occupant safety, and effective asset protection. If unsure, check with your local building inspector before making a final decisions in the implementation of the fail safe vs fail secure access control.
