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Informative White Paper Discusses Flame Detection Best Practices

Most of us have seen footage of devastating explosions or fire disasters at chemical processing plants and oil refineries. Many industrial facilities house large quantities of flammable or explosive fluids on site for use as feedstocks or fuels. Even when best practices are followed, equipment failure and operator error allow these substances to leak from their housing and ignite. Fortunately, many incidents are identified early by flame detectors that activate automated fire suppression systems, quenching a blaze before the destruction becomes newsworthy.

 The topic of fire prevention is explored in a recently released white paper from Emerson entitled “Flame Detectors: Key to an Effective Fire Suppression System.” As the title suggests, the installation of appropriate flame detectors is critical in mitigating the risk of uncontained fires.

Numerous fire detection technologies exist including smoke and heat detectors. These detectors require a fire to progress from ignition until concentrations of combustion products are detectable by a sensor. This is especially problematic in outdoor environments common to refineries and other chemical facilities.

Flames and their resultant hot gases generate electromagnetic radiation in ultraviolet (UV) and infrared (IR) wavelengths. The detectors sense light emission at these wavelengths with intensity patterns common to open flames, signaling the presence of a fire at the onset of combustion. In this way flame detectors provide an alternative means of fire surveillance with reduced response times compared to those of traditional smoke detectors.

A variety of factors must be considered when implementing a flame detector network such as the environment to be monitored and the identity of the fuel. Emerson offers a range of sophisticated detectors in the Rosemount 975 Flame Detector family that are tuned to different wavelengths of light. Since the chemical composition of a fuel determines the characteristics of radiation emitted, detectors that are best suited for ignition of probable fuels should be selected. The chosen detector should also be immune to the most common sources of false alarm such as arc welding, halogen lamps, and electrical discharges.

Even a properly selected flame detector cannot create an effective safety system by itself. Much like surveillance cameras, flame detectors must have a clear line of sight to hazardous areas. Likewise, the distance and angle of the detector from the spot of flames affects its sensitivity. Thus, to improve odds of detection success, a network of devices should be employed with overlapping detection that spans the entire high-risk zone.

If correctly chosen and installed, a flame detector system helps ensure minimum damage to personnel, property, and profitability through rapid detection of an incident while avoiding triggering false alarms.

For more details on the Rosemount 975 Flame Detector family and tips on installation, read the full white paper here.