Insects, Pets and Absent Mindedness
Recently I read an article on the causes of false alarms and at first dismissed it as somewhat bizarre. Then I looked again as it was commissioned by Which Magazine.
While they don't fit alarms on a daily basis, I assumed they were not daft and as they carry out studies on a daily basis, must have some valid and credible statistics I could gleen.
According to their report a whopping 30% of alarm activations are caused by insects. Next on the list is 22% by occupants and only 7% by animals.
Now, I'm pretty sure myself that pets cause a lot more activations than 7% and insects aren't that prevalent in the household that they're going to cause 30% of this havoc.
PIR sensors work by detecting heat which must move across the sensor and trigger it a number of times. Insects, especially flying ones, must generate some heat but are basically cold blooded - so I'm a bit surprised to find them so high on the list.
In my experience the worse things for setting off PIR sensors are pets, foil baloons and sensors being positioned over heating appliances (radiators, boilers or fires).
If you have pets, insist on pet tolerant detectors and use a reputable installer who will position sensors both sympathetically and effectively.
Source: Which? Magazine