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4.22.22 – SSI –

Tech expert Bob Dolph is concerned over a comment thread in an online discussion about an installation. What would you do?

Recently, I came across an online discussion about a rather humorous posted workplace photo. It was a photo of a recently installed acoustical glass-break detector (AGBD) mounted on a drop ceiling, and next to it was a set of personal keys hanging in the metal ceiling tile support grid.

Now, those experienced techs in the audience will recognize what happened here. However, some newer techs might be questioning what the heck I am talking about. It is sadly often a common practice to trigger an AGBD by throwing a set of metal key next to the device and at the mounting surface.

The tingling of the keys along with the low frequency sound of the impact somewhat simulates the breaking of glass and is often enough to trigger the discriminatory sound detection of the AGBD. If the AGBD trips, is it ready for operation, right? More on this in a moment.

Some of you may remember the famous professional tennis player John McEnroe. He was known for his famous statement, “You cannot be serious,” when criticizing the decisions of the tennis match judges. While the meaning of this statement is slightly different than our AGBD situation, it brings up on big question for today’s tech, and that is, are you serious about your work as a security professional?

While I don’t agree with the practice, I would normally not make a big deal about a few humorous comments about keys being thrown at an AGBD for testing. However, in this case, I counted more than 80 replies stating that they often did similar actions to trigger an AGBD. As a security professional, this has my concern at the direction and attitude of many installers, that is simply get it up, trigger it and move on.

I realize that in many cases over the years with my articles and its readers I am, so called, preaching to the choir. All I ask is that you pass the word so that less knowledgeable techs take a new sense of seriousness about the professionalism of their work. Remember, we are dealing with often life-safety when we install security equipment.

If nothing else, improper installation and testing could be a liability issue down the road. I have yet to see a manufacturer that lists in its manual testing instructions that state, “throw your keys against the wall to test.”

You’ll notice that I refer to tossing keys as a “trigger” verification and not a true “test.” Yes, the device will trigger, but will it trigger when the windows in question are broken. One is dealing with physical nature of sound such as distance, the acoustics of room, window curtains and types of glass.

Most reliable professional AGBDs have an electronic glass break simulation tester and manufacturer’s manuals instruct on testing procedures. If you are a serious tech you will follow those procedures.

Believe me when I comment on this topic. When I was a young alarm dealer, I had a miss with an AGBD. It was a smash-and-grab with large display windows being smashed. The AGBD did not trigger. A very embarrassing moment for a young dealer.

How can that be with such large windows? I thought it was equipment malfunction, only to realize years later that it was probably too loud a sound and saturated the devices detection circuit. I learned this when conducting a nationwide AGBD testing program for the second largest security company in the United States at the time.

TECH TALK TIP: Very loud glass break sounds may not trigger even some of today’s AGBDs. You will not see anything in the manufacturer’s specs relating to maximum dB sound levels. Make sure to always have installed a secondary means of detection, such as PIR motions to compliment intrusion detection.

Another good example why techs should be serious about something as simple as a basic AGBD install is laid out in the book, “The Alarm Science Manual,” by forensic alarm expert Jeffrey Zwirn. Windows in a garage were broken by a burglar. The window curtains attenuated the sound and the installed AGBD never tripped. The burglar entered the house and someone was killed. Material like this book is required reading for any serious alarm professional.

Now that I have your attention, you should be asking what you can do to be a more serious professional. This falls in every area of the security profession. We talk a lot about techs here but being serious in security sales is just as important.

Don’t cut back on equipment and services being offered. Give the customer a choice on the equipment you suggest and explain why. You might be surprised when they express their appreciation that you have their health and safety in mind. If they want to cut corners on equipment, make sure to get something in writing.

(Image: Roman Samokhin/stock.adobe.com)

Tool of the Month

If you are serious about your installs, then you must document your work. This month’s tool is simply your cellphone. Make sure to take photos of your work, including wiring, and save.

The DIY crowd these days are changing and going into system installs. Make sure you are covered in case a future issue arises.