Rail-safety rules announced Friday would phase out older tank cars used to transport crude oil and impose new restrictions on oil shipments, but several federal lawmakers from Washington said those steps don’t go far enough.

Up to a dozen trains pass through Snohomish County every week, each carrying more than 1 million gallons of Bakken crude to refineries in Skagit and Whatcom counties.

The U.S. Department of Transportation’s long-anticipated rules require stricter manufacturing standards for tank cars beginning in October, and the retrofitting of older models. The agency also mandated phasing out older, more explosion-prone tank cars known as DOT-111s within three years. Other changes would force oil shippers to slow down trains in urban areas, use better braking systems on those trains and share information with local agencies about hazardous materials.

U.S. Sen. Maria Cantwell, D-Wash., called it “more of a status quo rule than the real safety change needed.”

“This proposal is slow to get the most dangerous cars off the rails and doesn’t address the volatility of the crude oil that’s being shipped,” Cantwell said. “With the level of volatility and explosions that we’ve seen around the country in the past several months, we want to be aggressive about protecting first responders and the general public.”

Regulators have struggled to catch up with the Bakken oil surge over the past four years. Derailments have caused explosions and oil spills this year in Canada, North Dakota, West Virginia and Illinois. A crude-oil train killed 47 people in the small Quebec town of Lac-Megantic when it crashed and exploded in 2013.

Cantwell has sponsored a bill that would phase out DOT-111 cars immediately. Newer tank-car designs have thicker shells, thermal protection, pressure-relief valves and other measures to lower the chances of an explosion.

The congressional bill would approve $40 million for emergency-response training programs. It also seeks to stabilize crude oil before transport, because of evidence showing that substances added during the process of extracting it from the ground make it more combustible.

“We have a number of incidents showing how volatile and deadly this is, but they’re still shipping it because they don’t want to take it out,” Cantwell said.

The U.S. departments of Energy and Transportation are planning a two-year study into how the chemical properties of crude oil affect its combustibility during rail accidents.

At the state level, a rail-safety bill the Legislature passed last week awaits Gov. Jay Inslee’s signature. To improve readiness for potential accidents, it would require advance notice to emergency responders of oil-by-rail shipments. The bill also would impose a per-barrel tax to help pay for safety and planning measures. As is, that tax is only imposed on oil that arrives by ship.

The new federal oil-by-rail regulations were developed in conjunction with Canadian authorities.

Washington Democratic U.S. Reps. Rick Larsen and Suzan DelBene joined Cantwell in calling for additional work to further oil-train safety, beyond what federal transportation officials have outlined. Larsen also said he plans to seek more money to improve at-grade rail crossings, a source of major concern in Marysville and Edmonds.

Noah Haglund: 425-339-3465; nhaglund@heraldnet.com. Twitter: @NWhaglund.