Exploding suburban meth labs are old news. The latest trend in drug-related detonations: hash oil explosions. So warns FEMA in a recent weekly Bulletin of Fear (aka “InfoGram” for emergency services personnel).

As FEMA explains, “Some explosions in residences and hotels around the country are being traced back to a process using butane to extract and concentrate compounds from marijuana.”

What madness is this? you ask. Since when does marijuana lead to explosions (other than when a Cheetos bag is opened too quickly)?

Basically, hash oil is derived from cannabis plants by soaking them in butane (you know, lighter fluid) and then carefully boiling off that butane leaving hash oil behind. The key word here is “carefully.”

As Wired eloquently puts it:

Butane is highly flammable and it tends to sink, meaning that if you use it indoors or don’t ventilate well, you’ll run into serious trouble. Let some butane puddle in your living room, throw in a thoughtless spark from a cigarette, stove, or — dare I suggest — bong hit, and suddenly your apartment is missing a wall.

There’s some good news. Unlike meth production, which leaves behind uninhabitable homes and seriously messed-up users, hash oil production, while dangerous, doesn’t taint the property (or wreck the users — the resulting drug is akin to really high quality pot, according to Wired.)

So while disclosing that a home used to be a meth lab will probably be a new law this year, at least you won’t have to ask if anyone ever made hash oil. On the other hand, the giant hole in the wall might be a hint.