So you're trying to keep your people safe and you've bought a new hazarardous gas detector or two or three or twelve. No doubt you've got a combustible (LEL) sensor in whatever you bought since you're likely to run into a flammable gas or two. But just what flammable gas
So, knowing this, the portable four gas detector manufacturers have to also realize that neither their customers are not always going to know what type of flammable gases they're going to encounter in the field. Some do. Say you work for a propane delivery company, or are part of the Hazmat response team for a propane company. You're most likely to see propane. But that's not always a given, since propane delivery companies typical have storage depots full of diesel fuels for their trucking fleet. So you see the problem.
Because of this, some detector companies factory calibrate their combustible sensors with methane since this is a likely gas to encounter, and if a sensor is comprised, it will lose the ability to calibrate quicker than it will with the other gases. In other words, by calibrating to methane, so the thinking goes, you'll be able to detect a compromised sensor more quickly. This is a smart idea.
Other companies factory calibrate their portable combustible detectors to pentane so that they will be more sensitive to methane, i.e., they'll go off more quickly. This also has some good points.
Factory calibrating with propane like some portable gas detector companies do has less to recommend it, and is kind of the bottom curve on the good idea chart.
And all combustible gas detectors have cross-sensitivity factors that you need to be aware of- and you should be aware that they're not always accurate. More on that next time.