As a safety professional, you want to purchase flame detectors that best meet your facility’s particular needs. There are many things to consider when researching a fire detection system. When it comes to flame detection, the most popular systems use optical methods to detect flames.

Two common optical flame detector types are:

1. ultraviolet/infrared (UV/IR)
2. multi-spectrum infrared (MSIR)

UV/IR and MSIR flame detectors are sensitive to more than one band on the energy spectrum and therefore are less likely to produce a false alarm. Both technologies function well either indoors or outdoors and provide a reasonably fast response time.

So which type of detector should you choose? That depends on several factors:

• What kind of fuels does your facility employ? Alcohols? Gasoline? LNG/LPG? Solvents? Something else? Understanding your fuel’s flammable properties will help you determine the optical flame-detecting technology you need.
• Do other types of radiant energy exist in your facility, such as arc welding, hot objects, or direct sunlight? Your flame detectors should be able to distinguish between these non-fire energy sources and real flames. Typically, MSIR detectors provide the best immunity to these types of false alarms.
• How high is the risk of air-borne particulates should a fire occur? Smoke, oil, grease, and some chemical vapors can reduce a UV/IR unit’s detection range, so if, for example, heavy smoke is a concern, you should consider MSIR technology.
• Can the detector be placed near the potential ignition source or must it be located relatively far away? How wide an area should the device monitor? Different UV/IR and MSIR units offer varying detection ranges and fields of view (FOV). Match your environment with the corresponding device specifications for the best coverage.

For more details on these considerations and others, such as false alarm immunity and self-test diagnostics, please download our How to Select a Flame Detector whitepaper.