To provide a method and device for detecting hydrocarbons, except methane, in gases which dominantly or substantially contains hydrogen, methane, and hydrocarbons except methane.

This method for detecting hydrocarbon except methane in the gases dominantly or substantially containing hydrogen, methane, and hydrocarbon excepting methane includes a stage for collectively detecting hydrocarbon in the gases and providing a first value for the collectively detected hydrocarbons, a stage for burning the hydrocarbons except the methane, a stage for detecting methane in the gases and providing a second value, and a stage for computing the amount of the hydrocarbons, except methane from the difference between the first value and the second value. In addition, this invention concerns the device for executing the method.