Having recently shared our video on pellistors and how they work, we thought it would make sense to also post our video about PID (photo-ionisation detection). This is the technology of choice for monitoring exposure to toxic levels of another group of important gases – volatile organic compounds (VOCs).
Gas detectors are there to save your life, whether it is a fixed system or a portable detector, keeping them well maintained is an important part of ownership.
Our guest blogger this week, Julian, has put together simple steps to ensure your gas detector is up for the job as and when it’s required.
After last week’s comparative levity, this week, I am discussing something rather more serious.
When it comes to detecting hydrocarbons, we often don’t have a cylinder of target gas available to perform a straight calibration, so we use a surrogate gas and cross calibrate. This is a problem because pellistor’s give relative responses to different flammable gases at different levels. Hence, with a small molecule gas like methane a pellistor is more sensitive and gives a higher reading than a heavy hydrocarbon like kerosene.
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.
Crowcon’s expert, Chris is here to answer your question
There are lots of reasons why a portable gas detector may not react to gas, some of which may not be obvious when you pick up a unit. The safest way to make sure your gas monitor is working is to ‘bump’ test it.