London — Last Wednesday's oil rig disaster in the North Sea has raised questions about the design of the mammoth, deep-sea platforms that have pumped record levels of oil from offshore fields for more than a decade. Armand Hammer, chairman of the Los Angeles-based Occidental Petroleum Corp. which operates the Piper Alpha rig where the explosion took place, has acknowledged that the disaster showed a design deficiency. His company's officers, however, insist that the platform conformed to industry safety standards, and the rig passed an annual inspection by Britain's Department of Energy only a week before the accident occurred.
The explosion on Piper Alpha, in the North Sea 120 miles northeast of Aberdeen, Scotland, was the world's worst oil accident and claimed 17 lives with 149 missing and presumed dead. Sixty-four crew members survived, many under treatment for injuries.
The fire continued out of control yesterday as well-known Texas firefighter Paul ``Red'' Adair was forced to delay attempts to cap the pipelines feeding the platform and isolate the rig from surrounding oil and gas fields.
A veteran firefighter, now in his 70s, Mr. Adair indicated that he too was shaken by the ferocity of the accident.
``I've never seen anything like it,'' he told reporters in Aberdeen.
All of Piper Alpha's safety features and rescue equipment proved useless in the disaster as the helicopter rescue platform was blown apart and lifeboats were destroyed in an explosion which one survivor described as an ``atom bomb.'' The 34,000-ton platform, now sloping at a 45-degree angle and sending up billows of black smoke, went into operation in 1976 and cost almost $1 billion to build.
Piper Alpha was one of the first platforms in the North Sea and one of the largest, producing some 125,000 barrels daily. It accounts for two-thirds of Occidental's North Sea production and, linked with surrounding fields which fed through its pipelines, it accounts for 12 percent of total North Sea production. The surrounding fields are now shut down, and company officials say it could be a year before Piper Alpha is back in operation.
The cause of the explosion is believed to be the newly installed gas compression facilities which compress gas from undersea wells and pipe it ashore at 2,000 pounds per square inch or reinject it back into the wellhead to maintain pressure.
Experts say a sudden surge may have caused a leak and explains the screaming whistle sound which crew members say they heard seconds before the explosion.
After showing Prime Minister Margaret Thatcher his company's offices Friday, Mr. Hammer told reporters in Aberdeen that it was a mistake to locate this dangerous facility directly below the crew's quarters.
``Mrs. Thatcher and the company think that when we complete our inquiry and the government complete theirs, it may well be that the living quarters for the men will have to be moved from the precarious position they are now in,'' he said.
Many crew members were trapped in their living compartment, and the suddenness with which the entire platform was engulfed in flames and torn apart by secondary explosions made timely rescue impossible.
A sizable rescue effort, including assistance from NATO naval forces operating nearby, ended over the weekend after hopes were given up of recovering more crew members from the sea.
Some British oil rig designers, according to the Sunday Times, have proposed segregating worker accommodations on a separate platform from the drilling and processing operations, linking the platforms by bridges. But the cost of oil platforms is already extremely high, and companies have resisted making expensive modifications to meet safety standards not required by regulating authorities.
A former safety manager for Occidental, Jack Donaldson, told a Scottish newspaper that he had recommended safety measures for Piper Alpha after a gas explosion four years ago. He claimed that the recommendations were not accepted because it would require shutting down the platform for six weeks and losing revenue. The British government is under pressure to release the report on that incident which was not made public.
Occidental and Britain's Department of Energy are conducting separate inquiries into the Piper Alpha disaster. But investigation is made difficult because of the destruction of Piper Alpha's control room with its computer printouts showing pressure readings for pipelines and equipment in the complex platform. The accident brings to more than 500 the fatalities from oil-field operations during the 17 years oil and gas have been recovered in the North Sea.
Insurance market analysts in London have said that the Piper Alpha disaster could cost the insurance industry $1 billion in claims and could considerably raise insurance premiums for the oil companies.