A man who suffered severe burns to 12 percent of his body when butane fumes ignited while he was making hash oil, demonstrates how he made the marijuana concentrate, at his home in Denver in May 2014. (Brennan Linsley, Associated Press file)

Oregon man burned in blast making hash oil sues butane businesses

PORTLAND, Ore. — An Oregon medical marijuana patient who was badly burned in an explosion while he was legally using butane as a solvent to make hash oil is suing the makers and sellers of the fuel.

Kevin Tveisme, 28, of Portland, was injured in 2013 when his furnace clicked on, igniting butane vapor. The explosion destroyed his garage and injured a friend, Joseph Westom, who died 18 days later.

Treating marijuana with butane as a solvent extracts the potent hash oil at a low cost, but butane vapor is volatile. Explosions have become more common with the spread of legal medical and recreational marijuana.

As a medical marijuana cardholder, Tveisme was allowed to make hash oil under Oregon law, the lawsuit says.

Although the butane canisters had a “flammable” marking, the lawsuit says, the butane should have come with stickers and instructional brochures specifically warning of the volatility of the butane’s vapor.

The lawsuit also says the odorless butane should have been treated, like natural gas, with a smelly chemical to make its dangers obvious.

The lawsuit was filed Wednesday in state court in Multnomah County. It seeks $11 million in damages.

The suit was filed against a dozen defendants, including Shell Oil Products, a California-based distributor, and a Shell station in southeast Portland where the lawsuit says the butane was purchased. The owner of the store couldn’t be reached for comment.