In this study, a measurement system for a gaseous fire extinguisher bromotrifluoromethane (Halon 1301) was developed, using a quantum cascade laser (QCL) at ~8.280 μm. The performance parameters of this system were also analyzed. Much higher sensitivity and faster response time were achieved compared to non-dispersive infrared (NDIR) sensors and differential-pressure method. A response time of 90 ms from 0% to the targeted concentration 6% was obtained. The detection limit of 500 ppm was obtained with a short optical path length of 2.8 mm. In conclusion, the proposed system can be applied in the airworthiness certification test of an aircraft fire suppression system.

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http://dx.doi.org/10.1364/OE.27.008838DOI Listing

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