Carl Nix

A Gallup poll in 2017 showed that 64 percent of Americans were in favor of legalizing marijuana.

Today in the United States, recreational marijuana is legal in nine states and medical marijuana is legal in 29 states. Experts predict that the legal marijuana market will reached nearly $25 billion in sales by 2021 as more states pass legislation making marijuana legal.

Why am I writing about marijuana use when this column is about fighting fires using thermal imaging technology? The changing landscape of marijuana use poses a significant risk to firefighters who are responding to a fire call and find themselves in the middle of a grow house. Firefighters need to be aware of the dangers lurking inside a grow house to help protect them from a situation that could turn disastrous. When you first arrive on the scene, these homes look like every other house in the neighborhood from the outside. It’s what’s happening inside that puts firefighters at risk and where the use of thermal imaging technology can have life-saving effects.

Once the firefighting crew arrives on a scene and prepares to attack the fire, it should be common practice for a firefighter to grab the thermal imaging camera (TIC) off the truck and begin to perform size-up. Always start at the roof level with your TIC, checking the chimney, vents, and eaves before working your way to the attic and walls (include doors and windows). Be sure to check the crawlspace, basement areas, and dryer vent locations with the TIC. The TIC readings will be the first indication to the firefighting crew that this structural fire call may not be your typical call.

If your TIC screen is showing an excessive amount of heat coming from the chimney, vents, or basement area, it’s time to start questioning what is happening inside the home. Use your TIC to compare the heat signatures you are seeing to the heat signatures from neighboring structures to give you a baseline. After this comparison, if your TIC is still reading excessive heat coming from inside the structure, it’s time to alert the utility and police departments that you suspect a grow operation.

The police are aware of the dangers inside a grow house and will advise your firefighting crew of the potential risks they are facing including fortified doors and windows, booby traps, and unknown hydro sources from bypassing the meter or generator. As the firefighting crew enters the structure, it’s critical to proceed with caution and use the TIC for safely navigating obstacles such as low-hanging wiring and ventilation ductwork, which can entangle and entrap firefighters. The excessive heat created in a grow house is from the sodium vapor bulbs used, which can range fr