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Feb 14 2017

Man-Traps in Schools

Category: Egress,News,School Security,VideosLori @ 11:34 am Comments (5)

This morning I found an article in my news alerts:  Roxbury Eyes Spending $580K on “Man Traps” for Schools.  My first thought…”Oh. No.”

A man-trap is another term for an interlock, and interlocks are designed as a group of two or more doors that are part of a vestibule.  When one door is open, the other doors can not be opened.  There is more information about interlocks, including a video, in this blog post.

A few years ago, I read a proposed set of school security standards.  The standards called for man-traps in various locations in school buildings, which could be used to isolate and “trap” an active shooter.  In my opinion, this is a terrible idea.  The chances of containing an active shooter alone (without hostages) in a man-trap are minimal, compared to the risks involved with a man-trap’s potential for deterring egress and evacuation.

I’m hoping that the term “man-trap” is being used incorrectly in the article, and that the proposal is to add security vestibules, not interlocks.  A security vestibule would consist of two sets of doors which are typically locked on the access side, and which allow free egress at all times.  Security vestibules, along with personnel and processes to evaluate visitors before they enter a school, can be one of the best tools to prevent unauthorized people from gaining access.

Although I do believe that the term man-trap has been misused (as in this TIME Magazine article from just after the Sandy Hook shooting), the idea of locking egress doors in schools has been discussed as a recommended practice.  The video below shows a pair of doors with panic hardware, which a consultant describes as electromagnetically locked.  Although the doors are designed (and likely required) to allow free egress, they are locked by the security system when the intruder enters the building.  This is not compliant with the model codes, and I don’t believe that it is practical or safe.

When we’re talking about school security, let’s make sure to use the correct terminology…”security vestibule” – YES!  “Man-trap” – NO!  We can not forgot about egress and evacuation in a rush to secure our schools.  There ARE code-compliant options available.

Update:  This morning, I emailed the security director who was quoted in the article and explained the difference between a man-trap and a security vestibule.  He responded and said that there are fire marshals and building inspectors involved in their plans, who will ensure that the vestibules are code-compliant.  In this case, it seems like there was just a mix-up in terminology so that’s good news!

5 Responses to “Man-Traps in Schools”

  1. Scott Foley says:

    We have been doing a lot of Security vestibules recently and never had in the past,I have incorrectly heard the man trap phrase used quite a bit .
    Thank you again for educating me.

  2. Jamo Ladd says:

    very interesting. Question. What is to keep an innocent person from being trap in the vestibule with the criminal? Video shows a custodian/security sitting at a desk, however, he sounded the alarm and locked the doors instantaneously and not looking around. (Granted he may have had a good sense that no one else was there), but what if a child or parent had been walking through the doors at the same time. do we now have a hostage situation that may be taken off in a car?
    Good concept but would think more studying needs to be done on this scenario.

    • Lori says:

      There’s nothing to prevent an innocent person from being in trapped in the vestibule. That’s one of the problems.

      – Lori

  3. Louise says:

    A few thoughts:
    Where did the man at the table go? The only way out is by the exterior door, all other doors are locked.
    Wouldn’t the bad guy take the man as hostage and order him to unlock the door or some other hostage scenario?
    A school that can’t afford a PA system probably doesn’t have money for this system.
    I think the system should also have an enunciator to tell the bad guy that the only exit is the way he came in.

    • Lori says:

      Maybe the security guy ran out the exterior door. The vestibule shown in the video may or may not be an actual man-trap, but they still can’t lock the doors with the panic hardware in the direction of egress.

      – Lori

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