A roller coaster accident that injured 25 people at Disney's California Adventure was caused by a faulty brake valve installed and inspected just days before the July 29 crash, state investigators said Thursday.
The critical report by the Division of Occupational Safety and Health said that the new exhaust valves had a higher failure rate than the parts they replaced. As in past accidents, the report also criticized Disney for not following maintenance procedures, though that did not cause the accident.
The crash occurred on a Friday night during the Anaheim park's peak summer season when one train crashed into another on the California Screamin' roller coaster, the park's signature attraction that propels riders through a silhouette of Mickey Mouse's head.
Disneyland Resort officials said they have replaced the defective parts, enhanced the braking system and will reopen the ride today.
They agreed with the state's conclusions about the cause of the accident, but defended their maintenance and testing procedures, blaming the part itself for the brake failure.
"By all engineering standards these parts were identical," said Rob Doughty, a spokesman for Disneyland Resort. "This is not a maintenance issue, it's a brand-new part failing.... The fault was with the design of the valve -- there should not have been a problem."
In a departure from past accident investigations, the state also ordered Disney to inspect similar brake parts at all its other parks -- including those outside California -- and implement the same corrective action. Disney officials took it a step further by issuing a bulletin about the valve failure to the entire theme park industry.
"This was a very unusual thing to have happen," Doughty said.
One train stopped on the tracks and was rear-ended by another. More than two dozen passengers were taken to hospitals, where they were treated for minor injuries and released.
According to the report, the accident occurred shortly after Disney maintenance workers replaced several brake parts on the ride because of "an ongoing problem with the air line leaking due to the age of the parts and deterioration."
The original valves had been manufactured by a company called Intamin, the report said, but Disney used a different brand because Intamin parts were unavailable. The second brand, Legris, was "more prone to malfunction," state investigators said. In addition, it was made of a different material and was a different diameter.
