How long is a piece of string?

A common question to which the answer is dependent upon other factors.

A smoke detector is the same as any other product in the real world, it deteriorates over time and the speed of this is dependent upon two fairly obvious factors;

1. The environment that it is installed within  – In dirty environments it will not last as  long as a clean room

2. Has it been maintained? – Your car requires maintenance to keep it working efficiently and accurately, so does your fire alarm system.

To comply with BS5839 Part 1 2002 +A2, Section 6 point 45.3 subsection (n)  which requires the manufacturers guidance to be followed, the devices should be replaced in accordance with the manufacturers guidance.  I have added an extract below which covers this point.

The Signs

If you start to experience false alarms on your system or the number of calls to site to investigate faults with the devices increase then you may want to ask the question of your maintenance company.

Most, if not all, manufacturers label their devices on the inside or underside of the detectors, for example Apollo Fire Detectors have a series of labels on their products and have produced a guide for reading the date information.

If you have started to experience false alarms this could be due to the age of devices or through contamination of the detector internally, if you allow this to continue, in a very short time this will reduce the effectiveness of the system to evacuate the building as unwanted alarms cause a general mistrust in the systems integrity.

“That blinking fire alarm has gone off again” followed by inaction, which has the same effect as not having a fire detection and alarm system in the first place.

If the age is not found to be the issue then you may need to have the device chamber cleaned, which may require dis-assembly or could be as simple as being blown through with compressed air.  If this is a consideration then please make sure that you consult the services of a qualified and experienced engineer and also note that some devices can not be taken apart and can only be cleaned and re-calibrated by the manufacturer.  When you look at the economics of this you might as well just replace the product that is causing the issue.

The Manufacturers advice

Series 65 Optical Detector

Apollo Fire Detectors (for example) advice is that the product operating life is 10 years based on the operating life of the component manufacturer and that they should be replaced after this time.