Gov. Gavin Newsom said California officials are starting to review safety records of the aerospace firm whose pressurized tank in Garden Grove nearly exploded with a toxic chemical over the Memorial Day weekend, as well as other similar chemical plants.

“Obviously, all of us are now reviewing, and have been in real time, the safety records, not only of this site, but looking more broadly at other chemicals at other sites,” Newsom said in response to a question from The Times at a news conference where he signed an elections bill Wednesday. The review is “particularly highlighted by what happened tragically in Washington state, as well.”

The massive rupture of a chemical tank at a paper mill in Longview, Wash., led to the deaths of two people, with nine people missing and eight others injured, the Associated Press reported. Authorities said there was no hope of finding more survivors of the Tuesday accident at the Nippon Dynawave Packaging Co. It was one of the deadliest U.S. workplace accidents in years.

Newsom added that he was concerned about “some of the federal cutbacks to safety investments that have been made over the last year, federally, and are proposed in the president’s new budget. And I hope this tempers that likelihood that they’ll move forward with those cuts.

“I think they should be more robust in terms of those investigations, not less,” Newsom said.

When asked by The Times if more regulation of chemical plants might be necessary, Newsom said, “That’s what I’m suggesting, as it relates to the rules and regulations, all being reviewed, safety records being reviewed as well.”

State Sen. Tom Umberg (D-Orange) added at the news conference: “There will be legislation.”

The industry has been well aware of the risks of the types of chemical accidents that can lead to a thermal runaway reaction, posing the risk of an explosion. But experts for years have said companies have not learned from past mistakes.

Nearly 15% of incidents in the U.S. involving uncontrolled chemical reactions from 1980 to 2001 were thermal runaway incidents that involved rapid polymerization of a chemical, according to a study published in the journal ACS Omega, citing information from the U.S. Chemical Safety and Hazard Investigation Board.

In Orange County, the near-catastrophe was sparked by thousands of gallons of a highly toxic chemical in a failing pressurized chemical tank that was heating up at a Garden Grove aerospace firm, GKN Aerospace.

Authorities suspect that the cooling system responsible for maintaining the temperature of the tank filled with methyl methacrylate, or MMA, failed. MMA can be used to make hard, durable, lightweight and transparent plastics that act similar to glass, such as Plexiglass.

Experts believe the MMA liquid chemical, a monomer, began reacting with heat to become a solid polymer.

Each chemical reaction produced even more heat and raised the risk of a process called thermal runaway, when a reaction becomes out of control. That could result in a BLEVE, or boiling liquid expanding vapor explosion, which would have caused widespread damage and released toxic material into the air.

Some 50,000 residents in Orange County were evacuated. In the end, efforts to cool the crippled tank by spraying water on it were believed to have helped slow down the reaction enough to prevent an explosion or massive rupture in the tank that could have sent toxic chemicals flowing into waterways and the ocean. Eventually, officials found a crack in the tank and determined it had lowered the pressure inside, ending the threat.

Read more here: Los Angeles Times