Working in Technical Support, one of the most common questions from customers is for bespoke configurations of toxic gas sensors. This frequently leads to an investigation into the cross sensitivity of the different gases that the sensor will be exposed to.
Cross sensitivity responses will vary from sensor type to sensor type, and suppliers often express the cross sensitivity in percentages while others will specify in actual parts-per-million (ppm) levels.
Continue reading “Cross sensitivity of toxic sensors: Chris investigates the gases that the sensor is exposed to”
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.
Continue reading “Cross Calibration of Pellistor (Catalytic Flame) Sensors‡”
We have covered some serious subjects over the past few weeks, so I thought this time I would talk about something a little bit more light-hearted, at least on the face of it.
Back in January of this year, there were reports from Germany of an explosion – a herd of cows nearly took the roof off their barn because of the amount of methane they were releasing, when a static electric charge caused it to explode. The blast damaged the roof of the barn and one cow (out of about 90) received minor burns.
Continue reading “How best to study cow burps?”
A common question we encounter at Crowcon is when to use a pump or aspirator with a portable gas detection device. I’d like to share some thoughts about the use of personal detectors with pumps or aspirators as part of an effective confined space pre-entry check.
Continue reading “Getting yourself out of a hole”