Calibration Gases: Methane Versus Pentane
Selecting the right gas is a critical step in gas detector calibration. Two of the commonly used calibration gases are methane and pentane. Selecting the right gas depends on the application, other gases involved, and the sensor used to measure them.
Methane and Pentane
It’s important to understand the differences between methane and pentane calibration gases.
Methane and pentane are both hydrocarbons but differ in the number of their carbon bonds. Methane is the simplest alkane with only 1 carbon bond, while pentane has 5 carbon bonds. Since pentane has more carbon atoms, it can have structural isomers which methane cannot.
When is Methane the right choice?
Methane is the best choice for –
- natural gas operation
- when poisons or inhibitors are present
Methane has a very high vapor pressure, so it is stable enough to be mixed with air and still kept under high pressure. Methane also ignites at a higher temperature than pentane, and requires more energy for the sensor to detect it. For these reasons, certain gas mixtures might not read as accurately as others, and sensors may weaken earlier.
When is Pentane the right choice?
Pentane is best with flammable gases because it is more accurate. Its correction factors are lower than methane’s. This makes it more accurate. Pentane has a faster response to other gases which makes it the safer option. Pentane ignites at a lower temperature, compared to methane, so it’s not as tough on the sensors.
If you are looking to use Methane or Pentane as calibration gases, consider products from a trusted calibration gas company. If you are looking to buy gas detectors or calibration gases in Houston, TX, talk toGreen Light Safety at 832-262-9931 right away. Green Light Safety specializes in rentals, sales, service and calibration of Gas Detection equipment. With over 15 years’ experience in this industry, Green Light Safety specializes in rentals, sales and service of Gas Detection equipment as well as calibration of the equipment.