Geothermal energy is very attractive and has great potential for future development. Over the past 30 years, the geothermal industry has attempted to both improve the productivity of conventional geothermal fields and exploit new unconventional resources by developing techniques that improve steam production. Although geothermal power plants are known as an environmentally friendly form of power production, geothermal steam contains a number of non-condensable gases (NCGs). One of the gases is hydrogen sulphide (H2S), which, if not controlled, may cause safety, health, and environmental problems. Hydrogen sulphide (H2S) is a very toxic gas at normal temperatures. It poses a very serious inhalation hazard. There are numerous case reports of deaths, and most fatalities have occurred in relatively confined spaces (e.g., sewers, sludge tanks, cesspools, depressions on open land, or in buildings). ‘XYZ’ Geothermal Operation, located in West Java, Indonesia, is a company that produces steam and electricity from geothermal sources. The company implements the H2S hazard control in a systematic manner to prevent high-concentration H2S exposure
during normal operations and/or emergencies. In geothermal operations, sources of H2S are present in the wells, the operation process itself, and in the environment. Engineering control, administrative control, and personal protective equipment form the hazard control hierarchy that is implemented in geothermal operations to manage H2S risk. Hydrogen sulfide risk assessment should be provided in all facilities to help
mitigate H2S risks.
Keywords: geothermal, non-condensable gases (NCGs), hydrogen sulfide, hierarchy control