The terms “fail safe” and “fail secure” are used with electrified hardware to indicate the condition of the product when power is not present.  A fail safe lock will be unlocked on the access side when there is no power to the lock; a fail secure lock will be locked on the access side when power is removed.  Typically, the hardware will allow free egress as required by the model codes for most doors in a means of egress – it is usually the access side of the lock that is either locked or unlocked when power is applied/cut.

Some types of electrified hardware can be ordered as either fail safe or fail secure, or the function may be field-selectable.  Other products may only be available as one function or the other – for example, electromagnetic locks are always fail safe.  Fail secure products are more commonly-used than fail safe, as fail secure locks maintain the security of the opening even when power is cut.

So how do you choose whether to use fail safe or fail secure electrified products?  View the video and/or check out this Decoded article to find out, and then proceed to the review questions below.


Review Questions

1. For an electromechanical lock used on an exterior door of an office building, which type of product should be used in order to ensure security?

  1. Fail safe lock
  2. Fail secure lock

2. On a fire door in an exit stairwell serving a high-rise hotel, which type of electrified hardware may NOT be used?

  1. Fail safe electromechanical lockset
  2. Fail safe electric strike
  3. Fail safe electrified trim for fire exit hardware
  4. All of the above are acceptable

3. When an electromagnetic lock is installed on the main entrance door of a university building, which of the following describes the security condition during a power failure?

  1. The lock will be unlocked, allowing access to the building.
  2. The lock will be locked, and the door will be secure.
  3. The lock could be locked or unlocked, depending on whether a fail safe or fail secure mag-lock was ordered.

Answers: 1 – B, 2 – B, 3 – A