This is mainly used for gas treatment system in a nuclear power plant.
It applies as well to gas treatment of chemical power plant, where hydrogen has to be separated from other (toxic) components.
Note: a off-gas system is a complex system comprising several type of subcomponents: pipes, valves, filters, recombiners, separators, gauges, etc. However, their frequency in HIAD dataset is low and therefore, it was decided to aggregate all into one general term.
