Think back to the last time you wanted to test your flammable gas detector. You’re busy; you want something quick and convenient. An obvious answer is a cigarette lighter, isn’t it? A quick squirt of gas should do the job. Shouldn’t it?
If ‘the job’ is ruining your detector’s sensor at the flick of a switch, then yes!
If you use a cigarette lighter to test your sensors, you run the risk of:
- Rendering your sensor useless
- Compromising your warranty – carbon deposits are a dead giveaway for manufacturers who then won’t honour your claim due to incorrect testing
Why cigarette lighters are bad news for your sensors
Pellistor-type sensors (also known as catalytic beads) are used in industrial gas detectors to detect a wide variety of gases and vapours. The sensors are made up of a matched pair of ‘beads’ which are heated to react with gases. The sensors operate in the ‘Lower Explosive Limit’ (LEL) range, so provide a warning well before a flammable level of gas concentration accumulates.
Periodic and irregular exposure to high gas concentrations is likely to compromise sensor performance, and cigarette lighters expose the sensor to 100% gas volume. Not only that, but this exposure can potentially crack the sensor beads. Cigarette lighters also leave damaging carbon deposits on the beads – leaving you with useless sensors, and potentially putting your life at risk.
How to safely test your sensors
Bump test! Or you can calibrate using 50% LEL gas – but make sure you’re using the correct gas calibration adaptor from your gas cylinder, and that your cylinder’s flow is regulated to 0.5 to 1 litre per minute.