Description

Fire behavior characteristics (such as temperature, radiant and total heat flux, 2- and 3-dimensional velocities, and air flow) are extremely difficult to measure insitu. Although insitu sensor packages are capable of such measurements in realtime, it is also essential to acquire video documentation as a means of better understanding the fire behavior data recorded by individual fire behavior sensor packages. Therefore, coupling each sensor pack with a digital video recorder for simultaneous recording of video and insitu measurements allows viewing of the fire behavior as flames approach, envelope, and disperse past individual sensor packs. The limiting factor in this process is the amount of recordable digital video tape, typically 60 to 90 minutes of record time. This raises both tactical and safety-related concerns, requiring researchers to remain in proximity to the advancing fire in order to activate the fire behavior sensor and video packages. A new remote trigger that eliminates the need for human interaction in order to activate data collection hardware and video equipment has been designed and tested. This trigger system allows the fire behavior and video packages to stay in 'sleep' mode until a measurable rise in heat flux is detected. The detection activates the fire behavior sensor package to begin logging data and sends a wireless signal to activate the video package. The setup has been tested for range and interference in open and densely treed plots as well as in fire and nonfire settings, effectively and consistently activating the equipment at distances up to 100 yards.