Firefighters don’t really worry about getting high from the thick, fragrant smoke that wafts up from cannabis-related fires.

That’s because crews wear air tanks on the scene of fires, the Denver Fire Department told the marijuana resource site Leafly.

What firefighters do have to worry about is electrical wiring at grow houses and explosions at places where THC is being attracted from marijuana, department spokeswoman Melissa Taylor said.

“In the earlier times, when it was [recently] legalized, you had a lot of people who were not having buildings retrofitted for the electrical needs of a grow operation,” Taylor told Leafly. “Those presented significant issues with poorly fitted electrical wiring.”

Buildings not properly wired to handle the lights and energy needed to operate a grow house can pose major fire hazards and put the life of firefighters responding to incidents in danger.

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