Screwed Up Access Control

April 30, 2012
Access Control Involves the Total Opening including Loosen Screws

Maintaining access control using electromechanical or mechanical locks is dependent upon a number of factors. The system must be designed to prevent unauthorized entry by controlling access for all entry locations. Each lock must control access and to a reasonable extent, prevent unauthorized access. Once has been gained, the door hardware must be operable to automatically close and latch the door locking mechanism once access.

This is all well and good. But. I visited a housing complex that had three walk-in gates and a driveway gate that provided controlled access. Two clickers were given to each owner in order to operate the driveway gate. The walk-in gates were each equipped with an electric strike that was wired into a telephone entry system for the complex.

The problem was people who should not have access were gaining entrance at weird hours of the day and night. No one claimed responsibility for buzzing strangers in. No one seemed to be able to find out how. Every time someone checked the operation of the locks, no problem was found.

One day I was there visiting, and was told about the problem. We walked around checking out the operation of the telephone entry system, walk-in gates and the driveway gate. There was a sufficient gap around the walk-in gates.

I look at each walk-in gate edge to see if there was scraping or scratching; marks of forcible entry. There was none. I looked for tape over the keeper or rolled up paper or similar that people use to disable the operation of an electric strike. There was none.

However, looking further down the next gate, I noticed a horizontal line scratched into the paint. Looking closer, the line was scratched into the metal. Looking at the distance of the line from the walkway, it appeared the height was the same as the lower mounting screw from the electric strike.

As I was closing the gate, I saw the lower screw matched the line scraped into the gate. It appeared as if access was being gained by someone unscrewing the lower electric strike mounting screw. The screw head was loose, just enough that it affected the swing of the gate. Unscrewed a bit farther, the screw head would obstruct the closing of the gate. We guessed that after the persons who needed access came in, someone just tightened the screw.

The solution was to apply a red thread locker to the two mounting screws.

Have you had any unconventional method of unauthorized entry and what did you do to solve the problem?