NEW ORLEANS — Federal regulators did not need this week's explosion aboard a state-of-the-art rig to know the offshore drilling industry needed new safety rules: Dozens of deaths and hundreds of injuries over the last several years had already convinced them that changes were needed.
The U.S. Minerals and Management Service is developing regulations aimed at preventing human error, which it identified as a factor in many of the more than 1,400 offshore oil drilling accidents between 2001 and 2007.
What caused Tuesday's massive blast off the Louisiana coast is unknown. On Friday, Coast Guard officials suspended the three-day search for 11 workers missing since an explosion rocked the Deepwater Horizon, saying they believe the men never made it off the platform that erupted into a giant fireball.
Officials said four workers critically injured in the explosion are doing much better.
Coast Guard Rear Adm. Mary Landry said two of the workers are now out of the hospital, and a third is to be released within a couple of days. The fourth worker will remain seven to 10 days, Landry said.
Coast Guard Capt. Peter Troedsson said he spoke with all the workers' families about the decision to suspend the search before announcing it to the media.
"I'm a father and husband, and I have done this a few times before. It's never easy. Your heart goes out to these people," Troedsson said.
The Coast Guard says it will resume the search if any ships in the area see anything, but the workers' chances of survival had seemed slim well before Friday afternoon's announcement. "The time of reasonable expectation of survivability has passed," Landry said.
The 11 missing workers came from Texas, Louisiana and Mississippi. The Coast Guard has not released their names, though several of their families have come forward.
Steven Newman, CEO of Transocean Ltd., which owns the rig, said Friday night that eight of the nine missing Transocean workers were part of the crew that operated the platform's drills. The other two workers were employees of a BP contractor. Newman said the company would continue to assist investigators in determining the cause of the blast.
As the search was ending, oil company crews were trying to clean up the environmental mess created by the Deepwater Horizon, which finally sank Thursday.
The other 115 crew members made it off the platform.
An MMS review published last year found 41 deaths and 302 injuries out of 1,443 oil-rig accidents from 2001 to 2007. An analysis of the accidents found a lack of communication between the operator and contractors, a lack of written procedures, a failure to enforce existing procedures and other problems.
"It appears that equipment failure is rarely the primary cause of the incident or accident," the report said.
As a result of the findings, the MMS is developing new rules that would require rig operators to develop programs focused on preventing human error, an area that received relatively little attention in the past. The agency, which has yet to implement the new rules and is currently reviewing public comment on the proposal, also suggested audits once every three years on programs to prevent human error.