Gas Control Technologies, L.L.C.: Focuses primarily on installation of automatic natural gas earthquake shut-off valves and also on underground natural gas leak detection.

Exposure Control Technologies, Inc.: Industrial hygiene and engineering firm that specializes in laboratory ventilation.

Energy Control Technologies: Jardware, software, installations, and design services for turn key building automation system.

RESSAC Climate Control Technologies: Full service heating, ventilation, air conditioning, and refrigeration contractor providing installation service and maintenance to commercial customers throughout California

L S Gas Services: Leicester, UK specialists in central heating and combi boiler service and repair.

The Gas Trading Company Ltd: Surrey, South East UK based company specializing in central heating installation and service.

V F Gas Analysis Systems, Inc.: Providing mass spectrometers to the automotive, process and quality control industries throughout North America, for gas emissions and research and development.

GreenHouse Gas Online: Devoted to greenhouse gas and climate change news and science. Detailed information on the various greenhouse gases and on climate change issues. Also, contains up to date links to the abstracts of hundreds of greenhouse gas scientific papers.

ADC Gas Analysis Ltd.: Supply and manufacture infrared gas analysis equipment for use in: laboratory, emissions control, industrial process control. Full spares and service support.

Gas Heaters Online: Provides a variety of construction heaters, including natural gas, propane, and kerosene.