Understanding Fail Safe vs Fail Secure Lock Systems

Key Takeaway

  • Fail-safe locks are those that unlock the door when no power is supplied to them. 
  • If no power is supplied to Fail secure locks, the door is locked. 
  • The Kwikset Halo smart lock falls into the fail-secure category. It’s designed with a strong emphasis on security, making it suitable for applications where asset protection and security are paramount.

While dabbling with smart electronic locks, I’ve delved into an intriguing aspect of lock classification, specifically, the distinction between fail-safe and fail-secure locks. Since I didn’t know about it earlier, it piqued my interest as it introduced a new layer of knowledge about locks. I also found myself pondering which category best describes my Kwikset Halo which I installed a while ago.

So, I’m here to share my discoveries with you. In this article, we will explore the fundamental concepts of fail-safe and fail-secure locks, examine their operation and applications, and shed some light on the Kwikset Halo smart lock.

Fail Safe vs Fail Secure Definition

A fail safe lock is one which unlocks when there is no power to the lock. In other words, power is needed to lock these locks.

A fail secure lock keeps the door locked when the power to the lock is cut. Hence power is needed to unlock these locks.

Now let’s understand each of these categories in detail. 

Understanding Fail-Safe Locks

Understanding Fail-Safe Locks

These locks operate on the principle that, in the event of a power outage or system failure, they automatically unlock, facilitating both entry and exit. Fail-safe locks prioritize the safety of individuals both inside and outside a secured area.

Operation during Power Outage: 

The defining feature of fail-safe locks is their behavior during a power disruption. When power is lost, these locks automatically release their locking mechanism, permitting unrestricted access. 

Let’s imagine a situation where there’s a fire inside a building, and the power goes out. In this case, people inside the building need to get out quickly to safety. Fail-safe locks help with this because they unlock on their own, allowing people to exit without any delay or difficulty.

But that’s not all. Fail-safe locks also make it easier for emergency responders or anyone trying to help during an emergency. For instance, firefighters or paramedics can easily enter the building because the locks are not keeping them out.

In simple terms, fail-safe locks ensure that during a power outage, everyone can move in and out of a building safely and without any obstacles, which is crucial in emergencies like fires.


The usage of fail-safe locks is most common in situations where safety during emergencies is the top priority, and it’s crucial to have easy access to help. These locks are frequently found in specific places like emergency exit doors in public buildings, workplaces, and places where many people gather, such as theaters or stadiums.


  • Enhanced Safety: Fail-safe locks prioritize life safety by facilitating both entry and exit during emergencies, ensuring the safety of all individuals involved.
  • Compliance: They comply with building and safety codes that mandate unobstructed egress routes and facilitate access for emergency responders.
  • Ease of Use: Users do not require keys or special access credentials during emergencies, reducing confusion and potential bottlenecks for both entry and exit.


  • Security Trade-off: Fail-safe locks may be less secure than their fail-secure counterparts, as they automatically unlock during power outages, potentially allowing unauthorized access.
  • Limited Use Cases: These locks are best suited for specific applications where safety and ease of entry/egress during emergencies are critical. They may not be suitable for high-security areas like IT rooms where asset protection is paramount.

Understanding Fail-Secure Locks

Understanding Fail-Secure Locks

Fail-secure locks belong to a group of locking systems that put a strong emphasis on security rather than ease of access. These locks work on a straightforward principle: if there’s a power outage or a system failure, they stay locked. This means that a secured area remains restricted and cannot be accessed from the outside.

It’s important to note that while these locks restrict ingress (meaning people from the outside can’t get in), they typically do not restrict egress (meaning people from the inside can still get out freely). So, even in a power outage or system failure, people inside can exit without any issues for their safety.

Operation during Power Outage: 

The defining feature of fail secure locks is their behavior during a power disruption. In such situations, these locks maintain their locked position and need a power supply to unlock them. This design is important because it ensures that places with sensitive information, valuable items, or high-security requirements stay secure and inaccessible to unauthorized individuals, even when the external power source is disrupted. In simple terms, these locks prioritize security above all else, even when there’s a power failure.


Fail secure locks find extensive use in applications where security and asset protection are paramount. They are commonly installed in locations such as IT rooms, equipment storage areas, bank vaults, and facilities housing valuable equipment or confidential information. 


  • Enhanced Security: Fail-secure locks prioritize asset protection and security by remaining locked during power outages, ensuring that unauthorized individuals cannot gain access.
  • Asset Protection: They are ideal for securing valuable assets, confidential information, and high-security areas, where unauthorized access could have severe consequences.
  • Customizable Access: Access control systems can be integrated with fail-secure locks to provide controlled and monitored entry, enhancing security measures.


  • Safety Considerations: Fail-secure locks may not be suitable for areas where rapid egress during emergencies is critical, as they do not automatically unlock during power failures.
  • Reliability: Locations with unreliable power systems may need to consider backup power sources to ensure continuous security.
  • Complexity: Fail-secure locks often require more advanced access control systems, which can be costlier and more complex to install and maintain.

Is Kwikset Halo a Fail-Safe Lock or Fail-Secure Lock?

Is Kwikset Halo a Fail-Safe Lock or fail-Secure Lock?

In my opinion, based on my recent installation and understanding of lock systems, Kwikset Halo can be categorized as a fail-secure lock. Here’s my reasoning:

Firstly, when it comes to how this lock behaves when the battery is dead, it aligns with the characteristics of fail-secure locks. This means that even when the lock’s battery is depleted, the Kwikset Halo typically remains in a locked position. To open the door, you would usually need to provide an external power source or engage in manual unlocking. This feature seems to prioritize security above all else.

One notable point to mention is that like other fail-secure locks, Kwikset halo also allows for safe egress from the inside during emergencies by using the thumb turn. 

Frequently asked Questions

Q1. Do fail-secure locks require a manual key override for entry, or is there an alternative method for authorized access? 

Answer – The method of authorized access can vary depending on the specific lock and its integration with access control systems. Some fail-secure locks can be controlled remotely or through electronic access credentials, eliminating the need for manual keys.

Q2. Are there any legal or regulatory requirements that mandate the use of fail-safe or fail-secure locks in specific locations? 

Answer – Yes, building and safety codes often dictate the use of fail-safe or fail-secure locks in certain settings. For example, exit doors in commercial buildings may be required to have fail-safe locks to ensure easy egress during emergencies.

Q3. Are fail-secure locks compatible with smart home automation systems for remote monitoring and control? 

Answer – Yes, many fail-secure locks, including the Kwikset Halo smart lock, can be integrated with smart home automation systems, allowing users to control and monitor the lock remotely through smartphone apps or voice assistants.


The comparison between fail-safe and fail-secure locks reveals the fundamental differences in their operational principles and their respective roles in ensuring security and safety. Fail-safe locks prioritize quick egress and are vital in emergency scenarios, found in public buildings. In contrast, fail-secure locks emphasize security, remaining locked during power outages or emergencies and are common in high-security settings. The choice between them hinges on the specific security and safety needs of the environment. The Kwikset Halo smart lock is a good example of a fail-secure lock. 

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Hey! I am Mark. Though I am not a locksmith by profession, but locks have always fascinated me since my teens. And it all started when I got locked out of my house and I had to pick the lock. Since then it has become my hobby to learn more about different kinds of locks, understand their working and methods to pick them up. In due course of time, I have also become better aware of how installing the right lock goes a long way in ensuring iron clad security. I aim to share my passion (about locks) through this blog. If you are also passionate about picking locks or are just looking to beef up the security, hop on the ride.