Vaisala offers gas sensors in the form of CO2 probes and OEM modules, as well as carbon dioxide industrial transmitters, probes for harsh environments, HVAC transmitters, and portable hand-held gas sensors. Other gas sensors available include oxygen transmitters for industrial process measurements designed for oxygen monitoring in moist and aggressive process gases.

RAE Systems is a provider of gas sensors, volatile organic compounds (VOCs) monitors, and radiation-detection systems. They offer many gas sensors, including single gas, multi-gas, toxic, combustible and oxygen types. RAE provides portable, portable wireless, fixed, fixed wireless, and wireless area detection gas sensors.

CO2METER is an online seller of gas sensors, including many CO2 sensors and a wall-mount oxygen sensor. Their gas sensors can be used in OEM, science, research, university and engineering applications. CO2METER's dual-infrared (NDIR) gas sensors respond quickly to changes in CO2, are self-calibrating, and do not have a limited shelf-life.

RKI is a provider of many types of gas sensors. They offer portible monitors, fixed systems and specialty instruments for nearly every type of gas, including CO2, carbon monoxide, combustibles, hydrocarbons, hydrogen, methane, oxygen, propane, and VOC's.

Detcon manufactures fixed gas detection sensors for a wide range of industrial applications. The Model 700 is an intelligent sensor specifically designed for harsh environments. Models 500/600 feature Detcon's MicroSafe intuitive software. The Model 100 are high quality, low power, no frills gas sensors.

Det-Tronics builds gas sensors for detecting hydrocarbon and nonhydrocarbon combustible and toxic gasses, and provides hazardous fixed gas detection solutions. Det-Tronics offers gas sensors ranging from fixed infrared and catalytic detectors to display transmitters, gas controllers, power supplies, and gas control panels.

General Monitors manufactures gas sensors for many applications. Types of gas sensors available include hydrogen sulfide, combustible, toxic and ultrasonic gas detectors. Other products include photoacoustic monitoring, gas imaging, flame detectors, and fire and gas systems.

Sierra Monitor manufactures fixed gas detectors, gas monitors, flame detectors and hazardous gas detection systems for industrial markets. They provide combustible and toxic gas sensors, and oxygen deficiency and flame detection systems. Markets served include oil and petrochemical, water and wastewater, pharma, semiconductor, military, OEM's, and many more.

Kele is a supplier of specialty and gas sensors, including gas sensors for CO2, carbon monoxide, toxic, combustibles and duct smoke. Manufacturers include Bacharach, BAPI, GE, Honeywell, Kele, Sensata, Vaisala and Vulcain.

ENMET manufactures oxygen monitors, toxic and combustible gas sensors. Products range from compressed air line monitors to portable detectors and continuous multi-channel fixed systems. ENMET builds sensors for nearly any type of gas detection, including methane, oxygen, CO2, combustibles, toxic and hydrogen gasses.

SST offers four combustible gas sensors that can detect methane, propane, butane, ethane, pentane, LNG, LPG, hydrogen and others. The GC801 continuously displays gas concentration. The GC800 is installed in locations where the gas concentration display and relay contacts are not required. GIR901 gas sensors use IR (infrared) technology to sense gas. The GIR900 is an IR gas sensor installed in locations where concentration display and relay contacts are not required.

3M manufactures a variety of gas sensors for methane (natural gas) detection. They offer a 2-gas sensor pack that includes oxygen and combustible (10% LEL methane) sensors. 3M also offers a pack of 3 gas sensors that includes oxygen, carbon monoxide, and combustible (10% LEL methane) sensors. Two other "packs" are offered that include hydrogen sulfide detection.

Oxigraf is a supplier of Laser Diode Absorption Spectroscopy oxygen sensors for industrial, medical, aerospace and research applications. There are eight models available ranging from 6" to 9.25" in length, sensor modes of XC and LN, and oxygen ranges of 2% to 100% and 0% to 100%.

Endress+Hauser is a supplier of dissolved oxygen gas sensors. Seven models are available in both digital and analog configurations, for food, pharma, chemisty, power, inertization, water, wastewater and boiler feedwater applications.

Digital Control Systems is a provider of gas sensors to OEM's in the industrial, HVAC and medical-automation markets. They offer the Model 400 and the Model 300 Series CO2 gas sensors. The Model 400 CO2 Sensor is designed for laboratory use to measure and control percent-range CO2 levels. The Model 300 Series CO2 Sensor is designed for the OEM market and is designed for measuring CO2 in high concentration (1-100%) environments.

Honeywell manufactures two lines of CO2 gas sensors. The C7232 line are CO2 transmitters with 0/2-10Vdc or 4-20mA output and adjustable ppm ranges. The C7632 line are CO2 gas sensors with a fixed 0-2000ppm range and a fixed 0-10Vdc output, no adjustments necessary. Mounting options include duct mount, wall mount, and portable.

MSA manufactures Ultima MOS-5 hydrogen sulfide gas sensors. Standard include ATEX, CSA, FM, CE Marking, and FM certified to IEC 61508. These gas sensors are used in many applications, including chemical, electric power, food and beverage, nuclear, oil and gas, pharmaceutical, wastewater, and others. The Ultima MOS-5 detects hydrogen sulfide in parts per million (ppm) levels.

Pemtech is a manufacturer of gas sensors, including hydrogen sulfide, combustible, toxic, oxygen and CO2 gas sensors. Other products include monitors and controllers, wireless gas detection, process analyzers and calibration accessories.

Toxalert is a manufacturer of gas sensors that monitor levels of toxic, combustible, oxygen depleting, CO2, refrigerant and other types of gases. Applications include airports, bottling, fire stations, hospitals, parking facilities, HVAC, schools, and more.

BDC is a supplier of dissolved oxygen gas sensors. They offer the Honeywell DL424/425 DirectLine dissolved oxygen sensor with a direct 4-20 mA output and a 1/2” NPT conduit connection. They also offer the Honeywell DL5000 Equilibrium Probe that is unaffected by fouling or changes in sample flow, and offers reduced maintenance costs (no periodic replacement of anode or electrolyte).