Fail-Safe vs. Fail-Secure Locks – Which Is Right for Your Application?

Introduction

When choosing electronic locks for a building, one of the most important decisions is whether to go fail-safe or fail-secure. The choice affects both security and life safety, and it’s not always as simple as picking “the more secure option.”

Fail-safe and fail-secure locks behave very differently during a power outage. Understanding how each works — and when to use them — ensures your doors stay compliant, functional, and aligned with your access control system.

What Does “Fail-Safe” Mean?

How it works:

• Powered → Door is Locked

• Unpowered → Door Unlocks

Fail-safe locks use constant power to stay locked. If power is lost, the lock automatically unlocks, allowing people to pass through without presenting valid credentials.

Common Applications:

• Emergency exits and stairwell doors

• Doors on evacuation routes

• Double entry doors with double maglocks – A common setup in office lobbies, schools, and secured facilities. Both doors release automatically during a power outage or fire alarm to ensure safe and immediate egress.

Benefits:

• Ensures quick, code-compliant egress during emergencies

• Meets fire and building code requirements for certain doors

Drawbacks:

• Less secure during a power outage since the door unlocks without credentials

What Does “Fail-Secure” Mean?

How it works:

• Unpowered → Door is Locked

• Powered → Door Unlocks

Fail-secure locks use momentary power to unlock. In normal operation, power is applied briefly when valid credentials are presented — such as a card, fob, mobile credential, or biometric scan — then the door re-locks when power is off.

Common Applications:

• Main entrances using electric strikes or electrified locksets

• Server rooms, security offices, and restricted areas

Benefits:

• Keeps the door secure from the outside during power failures

• Works well with access control systems where entry must remain credential-based

Drawbacks:

• Must be configured for free egress on the inside to meet code

Which Is Best for an Entrance Door?

For most commercial entrances, fail-secure is the better choice — unless you’re using maglocks.

• Fail-secure (electric strike/lockset): Keeps the exterior locked during outages, requiring credentials to gain entry, while still allowing people inside to exit freely.

• Fail-safe (maglock): Required by code in most cases to unlock automatically during a power loss or fire alarm — meaning entry does not require credentials during an outage.

Examples:

• Retail store front door with an electric strike → fail-secure.

• Office building double entry doors with double maglocks → fail-safe. Both doors release when power is cut, providing immediate, code-compliant egress for occupants.

Factors to Consider When Choosing

1. Life Safety Codes & Fire Regulations – Local codes may dictate lock type.

2. Building Use & Occupancy Type – Hospitals, offices, and warehouses all have different requirements.

3. Integration with Access Control Systems – Ensure your hardware works with your chosen credentials (cards, fobs, mobile, biometric).

4. Security vs. Safety Priorities – Decide whether protecting assets or ensuring instant egress is the top concern for that door.

Conclusion

Both fail-safe and fail-secure locks have important roles in access control, and the right choice depends on the door’s function and compliance requirements.

• Fail-secure is common for entrances, server rooms, and restricted areas, where maintaining credential-based access during a power outage is critical.

• Fail-safe is often used on emergency exits, stairwells, and maglock entry doors, where quick release during an outage or fire alarm is required for life safety.

Instead of treating one as “better,” think of them as different tools for different applications — the key is choosing the right function for each specific door.

Have questions about which option fits your project? Contact Aames Lock today — our team can help you understand the requirements, review your application, and guide you toward the best solution for both safety and security.