lock fail safe fail secure


If you’re installing new electric locks to secure your property, you have a lot of options to choose from. An electric lock is the focal point of any modern access control system, and there are two main categories of electric lock: fail-safe and fail-secure. But what is a fail-safe or fail-secure lock? What’s the difference between the two, and how does that affect you and your building’s tenants?

In this post, we compare fail-safe vs. fail-secure locks. Then, we explain which type of lock you should use to secure different areas of your property.

This post covers:


What is a fail-safe lock?

A fail-safe lock is a type of electronic lock that depends on a constant stream of power to stay locked.

To unlock a fail-safe lock, you must disrupt the flow of power to the lock. So, when you present a valid credential — like a key or fob — at a door with a fail-safe lock, it momentarily disrupts the flow of power to the lock. After power is disrupted, the lock disengages and the door can be opened.

If there’s a total loss of power, the default state of a fail-safe lock is open. Locks that depend on electromagnetism, like magnetic locks or maglocks, depower during outages and are a common example of a fail-safe lock.

Fail-safe locks are so named because they keep people safe in the event of a power failure. By providing the ability to enter and exit a doorway freely, a fail-safe lock gives your tenants a larger range of mobility if they need to find the correct way out of the building in the event of a power outage.


Learn about the differences between electric locks and magnetic locks:


What is a fail-secure lock?

A fail-secure lock is a type of electric lock that you can unlock with a single burst of power. In contrast to a fail-safe lock, fail-secure locks don’t require electricity to stay locked.

When there’s a power outage, a fail-secure lock will remain locked from the side of the door that requires a credential to enter. However, you’ll still be able to open a door with a fail-secure lock from the inside.

Fail-secure electric strikes don’t grant as much freedom of movement in the event of an emergency, but they do provide a more secure way to manage access for spaces where security is a high priority. In the event of a power failure, a fail-secure lock stays closed and secures an area.

While it may seem counterintuitive at first, fail-secure locks help increase safety in certain circumstances. For example, fail-secure locks are very helpful during fire-related emergencies. Some stairwell doors or fire doors are equipped with fail-secure locks that seal an area off and prevent fire from spreading from one section of the building to another.


fail safe vs fail secure door


Recap of fail-safe vs. fail-secure

In summary, the main difference between fail-safe and fail-secure locks is their default state when they’re unpowered. A fail-safe lock is unlocked when it’s unpowered, and a fail-secure lock stays engaged when it is unpowered.


Watch how electric strike locks work:


Fail-secure vs. fail-safe locks for different areas of your property

Now that you know the difference between a fail-safe and fail-secure lock, you’re ready to decide which type of lock you should use for different devices at your building — like the intercom.

Fail-safe locks should be used to secure areas that building tenants constantly use. These are the areas that require tenants to have freedom of movement in the event of an emergency.

Use a fail-safe lock to manage access for areas like:

  • Main entryways
  • Rooftops
  • Stairwells
  • Garages

While fail-safe locks will help keep your tenants safe during an emergency, an intruder might take advantage and enter your building while residents are exiting. This is why it’s important to guard other, highly sensitive areas of your building with fail-secure locks that remain locked during a power outage. Fail-secure strikes are also a requirement for fire-rated doors, as mentioned in guidelines issued by the National Fire Protection Association.

Use a fail-secure lock to manage access for:

  • IT server rooms
  • Inventory closets
  • Package rooms
  • Fire doors



The choice between a fail-secure vs. fail-safe lock might seem insignificant. But, if you’re in charge of your building’s access control system as well as the safety and convenience at your property, it’s a choice with wide-reaching safety implications.

Generally, where convenience is a priority, choose a fail-safe lock. However, if you’re looking to emphasize security, choose a fail-secure lock.


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Ferdison Cayetano

I’m a proptech enthusiast from New Jersey who’s looking forward to the innovations that will revolutionize real estate.