NEW ORLEANS, USA — A Transocean employee who survived the Deepwater Horizon rig explosion testified at the Gulf oil spill trial yesterday that a subordinate killed in the blast was one of the workers who apparently missed signs that BP’s well was about to blow out.

Randy Ezell, the first rig worker to testify in person at a trial designed to assign blame for the 2010 disaster, said Jason Anderson was a “top-notch” toolpusher who would have done everything in his power to prevent the blowout.

Anderson was one of 11 workers killed on the rig, which was owned by Swiss-based Transocean Ltd and leased by BP PLC. The blowout of BP’s Macondo well ultimately spawned the nation’s worst offshore oil spill.

Ezell, a senior toolpusher, said Anderson and others on the rig, including BP supervisors, misinterpreted the results of a crucial safety test. Ezell said Anderson told him during a telephone call less than an hour before the explosion that it was a “good test” and that there were no signs of trouble for 30 minutes after the test.

Well data showed the first indication of a problem could have been spotted about 20 minutes before that call, plaintiffs’ attorney Paul Sterbcow said as he questioned Ezell.

“All I can tell you is Jason apparently misinterpreted what he was seeing,” said Ezell, who was one of Transocean’s top supervisors on the rig.

Ezell said BP’s well site leaders on the rig ultimately were responsible for deciding how the tests were performed and interpreting the results.

“We all knew it was BP’s well and he had the final say, the well site leader,” Ezell said.

Donald Vidrine and Robert Kaluza, who were BP’s well site leaders on the rig, were indicted last year on manslaughter charges and await a separate trial. They have pleaded not guilty.

Their indictment accused them of disregarding abnormally high pressure readings that should have been glaring signs of trouble just before the blowout. Anderson attributed the pressure readings to something he called the “bladder effect”, according to a presidential commission’s report on the blowout, but the indictment said that was a “scientifically illogical” explanation that Vidrine and Kaluza shouldn’t have accepted.

Ezell, who wasn’t present for the discussion about the test results, said he had never heard the term “bladder effect” and doesn’t know what it’s supposed to mean.

No Transocean employees have been charged with crimes in the April 20, 2010 explosion or subsequent spill, and the indictment doesn’t mention Anderson by name.

Ezell said he doesn’t know why Anderson and others were comfortable with the test results.

“I wish they were alive to tell us, but I don’t know what that reason was,” he said. “He didn’t tell me anything about a problem.”

Ezell also heaped praise on Anderson, saying he trusted him with his life.

“I still have the same confidence in Jason that I did before the incident,” Ezell said.

Ezell was off duty and in his room when he got a frantic call from an assistant driller who told him mud was shooting up from the rig floor and asked for his help.

“I was horrified,” he recalled.

Ezell was heading out to grab his boots and helmet when the explosion blew him 20 feet against a wall, leaving him covered in debris and disoriented.

Ezell, 57, helped two injured workers get off the rig safely. One of them had told Ezell to leave him and save himself. Justice Department attorney Michael Underhill asked Ezell why he didn’t.

“I stayed because it was the right thing to do,” he said.

In a daze, Ezell and dozens of other workers had to watch the rig burn from a supply vessel for hours before they were able to return to shore.

“You can’t understand the intensity of what we went through that night,” he recalled.