General Monitors-Gas and Flame Detection

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Meeting Hydrogen Hazards in Plant Environments

Ultrasonic gas leak detector offers extra layer of protection for hydrogen gas detectionGeneral Monitors and Gassonic provide a diversified technology approach for hydrogen gas and flame detection. The combination of fast ultrasonic gas leak detection with the capabilities of catalytic bead sensors and UV/IR flame detection offer an integrated safety solution that reduces gas leak and fire ignition hazards to improve overall plant protection.

Hydrogen is a combustible gas that is difficult to detect and easily ignitable on contact with open flames, electrical sparks, and static discharge. It is lighter than air and consequently challenging to detect in open, well ventilated areas. Moreover, hydrogen produces fires that radiate primarily in the ultraviolet, rendering them almost visually imperceptible in artificial or natural light.

Because of hydrogen’s unique properties, General Monitors and Gassonic offer a line of products well suited for the detection of this most abundant gas. The Gassonic Observer provides near instant detection of pressurized hydrogen gas leaks. It can detect the ultrasonic noise generated by the escaping gas regardless of ventilation rate, gas dilution, or the direction of the leak. The sophisticated microphone technology has a detection radius for hydrogen up to 8 meters from the detector at a leak rate of 0.01 kg/s. 

A distinct advantage of ultrasonic technology is that gas never has to make contact with the sensor to be detected which is particularly useful in high-pressure hydrogen applications. In addition, the Gassonic Observer features the Senssonic™ integrated acoustic self-test to prevent unrevealed failures from occurring.

General Monitors’ S4000CH and S4100C intelligent sensors are ideal for detection of low pressure sources of hydrogen or where accumulation of the gas can occur. Designed for use with General Monitors’ catalytic bead sensors, they are robust, reliable, and like the ultrasonic gas leak detectors, easy to install and maintain. Once in place, the detectors can operate for years with minimum maintenance, requiring only periodic gas calibrations to verify operation. Although all catalytic bead sensors are suitable for hydrogen detection, General Monitors has developed a specialized sensor for the exclusive detection of hydrogen gas, one which is resistant to the interference of other hydrocarbons. The S4000CH and S4100C intelligent sensors are an important complement to Gassonic ultrasonic leak detectors for the fast and reliable detection of hydrogen gas leaks.

For the detection of hydrogen flames, General Monitors has designed a hydrogen-specific configuration for our FL3100 UV/IR flame detector. This product monitors shorter IR wavelengths of 2.7 to 3.2 microns and senses the presence of hydrogen flames in less than 500 milliseconds. By monitoring in both the UV and IR spectral ranges, the FL3100 is exceptionally accurate and highly immune to false alarms caused by lightning, arc welding, hot objects and other sources of radiation. The device also offers a wide field of view for greater fire detection coverage. Like the Gassonic Observer, the FL3100 features a self-diagnostic feature to ensure the fail-safe operation of the unit. Known as continuous optical path monitoring (COPM), the circuitry self-checks the optical path integrity and electronics once every minute to ensure proper operation.

To provide customers with an increased level of safety, all three of the detection technologies are suitable for use within SIL 2/3 environments*. The integration of all these products for hydrogen applications provide additional layers of protection that is not obtained through the exclusive use of a single detection technology. The complementary nature of the products enhances detection efficiency, increasing the likelihood that a hazard is mitigated before it escalates. The high reliability, superior performance and rugged packaging of the Gassonic Observer, General Monitors S4000CH and S4100C, and General Monitors hydrogen-specific FL3100, make them ideally suited for the harsh environments of oil/gas production, petrochemical refining, and hydrogen gas storage and distribution facilities.

*FL3100: SIL 3 Suitable, S4000CH: SIL 3 Suitable with 4-20 mA output only or SIL 2 Suitable with Relays, S4100C: SIL suitable, Gassonic Observer: SIL 2 Suitable

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General Monitors, Inc.
26776 Simpatica Circle
Lake Forest, CA 92630

Phone: 949-581-4464
Toll Free: 1-866-686-0741
Fax: 949-581-1151

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