Printed from the blog of Lori Greene, AHC/CDC, CCPR, FDAI
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Nov 19 2014

School Guard Glass

Category: Glass,School SecurityLori @ 11:24 pm Comments (16)

I am cautiously excited about this product and I’d love your thoughts on it. According to this news report, the glass can be retrofitted in doors that currently have 1/4″ glass.  The FAQ page on the School Guard Glass website says that the glass kept the testing agent at bay for over 6 minutes, and has a cost of $1000-$1200 (installed) to replace the glass in one full glass door with the SGG4 product.  The SGG5 glazing kept the testing agent out for over 12 minutes, at a cost difference of about $18/square foot more than the SGG4.

Considering the typical response time by police and the average duration of these incidents, glass that could withstand 6 minutes of abuse would be a big step in the right direction.  The spec sheet on their website provides comparisons between various types of glazing.

So…what do you think?

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16 Responses to “School Guard Glass”

  1. Cda says:


    I guess one question is where would the glass be placed?

    And, the person just has to wait for someone to open the door

    • Lori says:

      I’d start with the main entrance and then the emergency exits. It’s possible someone could open the door but there are procedures in place to help with that.

  2. cda says:

    I guess the other route is why do they need clear doors???

    Install a good steel door???

    And the other item with installing this product is the frame? Can someone stick a crow bar and just pry a little to pop the bolt?

    It is a good idea, just a matter of how far does a school want to take security?

    • Lori says:

      Most schools have glass in their entry doors. It makes them look less like prisons.

      There will always be ways in, but delaying entry is the key.

    • Doug says:

      Steel doors rust and require constant maintenance. New aluminum mthemral doors can achieve U values of .40. Th trick is to make schools safe without making the schools look like bunkers.

  3. Joel Niemi says:

    Did the testing include firearms?

  4. Kent Krauser, AHC, FDAI says:

    Very interesting. Wonder how it performs with fire? Bic lighters, etc. This glass will lend itself well to the windstorm rating of full glass doors, etc.
    Looks like a great improvement!

  5. Cda says:

    You could paint them green and have signs ” welcome to the emerald city”

    Or other things you could do with a door to make it aesthetically pleasing. If they want light, put glass up high

  6. TJ says:

    Can’t they just pop out the glass stops and take the glass out?

    • Lori says:

      They’re looking for quick and easy access. I don’t think in the heat of the moment they’re going to take the time to take out the stops. And I’m not sure how easy it is from the outside.

  7. Eric says:

    It says on the website that guns are used. It also states that the bullets penetrate the glass but the glass stays in place. That may not be ideal but it’s better than nothing. Hopefully the impact will reduce the bullet speed and deflect it enough to minimize injury. I think it’s a great concept. 6 minutes is a long time and $1000 per door doesn’t seem that high at all. However, it’s been a while since I’ve done any bullet resistant glass. Can someone provide a comparison dollar figure for glass rated for .762 caliber?

  8. Khozema Kazi, AHC, FDAI says:

    I think 6 minutes of continuous hammering before the glass gives in, is worth it.
    The intruder may not always be knowledgable about breaching the opening thru prying/popping up the bolt or removing the stops. Seeing a full glass door would tempt the intruder for his first strike to enter. And hitting on the glass will also alert all, rather than the less noisy ways of prying or removing stop.

  9. Bob Caron says:

    How long does it take to get through standard laminated safety glass? I saw the end result of a fire department forced entry on a half glass door years ago and it looked like they had to have spent a bit of time getting a hole big enough to get their hand in there and open the door.

  10. Jon says:

    I have a couple of issues with this. First, the video shows five shots of only one (unspecified) caliber spaced what appears to be 10″ apart. ASTM-F1915 and UL standards for ballistic glass typically calls out up to five shots (for many calibers) in a pattern no more than 5″ apart so that couldn’t have been the test in the video. The website and video refer to a H. P. White test but neither include a reference for the actual test specification used. Most likely this is a test devised by the manufacturer and H. P. was paid to conduct the test. Nothing wrong with that but if my district Superintendent were to ask. I’d tell him to request the test specification used and H. P. Whites certification documents.

    Second, none of the tests I know of are real world. I’ve spent many hours on the range watching SWAT team members blowing holes in doors and glazing.

    I’d guess 20 seconds and 15 to 30 .762 caliber rounds concentrated in 4″ spread coupled with a few butt strikes and the bad guy would have his hand all over the door lock. The kicking, 2×4’s, bricks and bats all make an interesting video but I’ve yet to read a report where these are the typical weapons and tactics that have been used to kill children in schools.

  11. Jim Elder says:

    I discussed this product with the president of the company a year or so ago. Although i have not specified it yet, i plan to first opportunity. This product is not designed to be bullet resistant; in fact, its first job is not even burglary resistance. The guy is a glass manufacturer who was picking up his kids one day and had a “light bulb moment”: a retrofitable product that would delay the actual penetration of an intruder. He noted that it adds a 4 to 6 minutes to an intrusive entry. That is a lot of time; it also allows for “recognition of intent” sooner allowing more time for staff and police to react and respond. Most architects use tempered glass on or near a door (including classroom doors). The School Guard costs more, but it is the clear choice in new work; or, if you don’t want to mess with window film in existing lites.

    Ever since Sandy Hook (you recall that is how Adam Lanza got in), we should be rejecting tempered glass, particularly in areas close to doors or near walkways.

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