Bump testing is one of those topics that crops up again and again, but still not everyone gets the point. A gas detector may not respond properly to gas for many reasons. Bump testing is a quick and easy way to ensure yours does. Here is just one example of what can happen if you don’t bump test your equipment.
Calibration of gas detectors is vital to be sure that they are in good working order and able to alert the user to gas hazards in their vicinity. A calibration is a “resetting” of the detector’s response against a known concentration of target gas, in a balance of synthetic air or nitrogen. This will determine the relationship between the detector’s reading and the actual concentration of the component gas of interest. Adjustment involves modification of the detectors response to bring the reading into line with what is expected while exposing the instrument to the known source. This is fundamentally different to bump testing which is a brief exposure to gas in order to verify that the sensors respond within a specific boundary and the detector’s alarms function properly.
There are many reasons why a portable gas detector may not react to gas, some of which are not visibly evident to the user. When an instrument is turned on, you can see that the battery and display are working properly, but what about the internal electronics which play a critical role in protection? Do the sensors and alarms all work, have they been inhibited by using the wrong cleaning solution or have their openings become obstructed by mud? How do you know?
Following on from last week’s article, ‘Why do I need to bump test my instrument?’, I thought I’d give you a little more detailed information about what is a bump test and how to carry one out.