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Excerpted from The History of Oilfield Diving: An Industrial Adventure
by Christopher Swann (Oceanaut Press)
by Christopher Swann (Oceanaut Press)
The worst nightmare for a bell diver is the prospect of having to rescue an unconscious partner. Prompted by the spate of accidents in the mid-1970s, diving companies in the North Sea developed a variety of techniques for recovering a diver into a bell and resuscitating him. The Comex safety manual, for example, covered the question in considerable detail. In 1984 the manual proved its worth when Comex diver George Lawson, working from the semi-submersible drilling rig Dundee Kingsnorth, unwittingly cut into a gas pocket with an oxy-arc torch. The resulting explosion broke his Kirby Morgan SuperLite helmet at the chin, shattered the reinforced faceplate and ripped out two of the screws that held it to the fiberglass shell. Lawson was knocked unconscious. Not only did the explosion burst his eardrums; the shock wave went down his airways and into his lungs, causing a pneumothorax.
It took the bellman, Neil Wiggins, about five minutes to reach Lawson and open his constant-flow valve and two more minutes to haul him back to the bell. The return was arduous. First, because of the heavy bail-out bottle on the unconscious diver’s back, it was a constant struggle to keep him face down and prevent his helmet from flooding; second, unknown to Wiggins, Lawson's umbilical was hooked on one of the guide posts. Luckily, the operator of the small ROV which was monitoring the dive saw what had happened, which allowed the surface to direct Wiggins to unfoul it; otherwise, the added delay might have proved fatal.
As it was, by the time Wiggins pulled his partner into the trunking of the bell—helped by the ROV pushing from below—and hooked him onto the lifting device installed for just such an emergency, he could not find a pulse. Wiggins did not attempt to hoist him in. He applied 11 minutes of mouth-to-mouth resuscitation in the trunking and brought him back to life. Then he winched him into the bell.
Because salt water had affected a third of his lungs, Lawson was panting furiously. When he was brought into the chamber, he was breathing 60 times a minute, five times the normal resting rate at the surface.
Most of the doctors Comex hastily consulted expected him to die of secondary drowning. Secondary drowning occurs when lung tissue irritated by the inhalation of sea water reacts by oozing fluid, as a cut oozes after it has stopped bleeding, eventually filling the alveoli. Crudely put, the victim drowns in his own juice. Dr Philip James of the Wolfson Institute in Dundee, who took charge of the case, was prepared to take draconian measures, however. He directed that Lawson be given oxygen at a partial pressure of up to 3 atmospheres to oxygenate those parts of his lungs that had not been flooded; and, banking on the fact the patient was young and fit, injected with massive doses of steroids—in the event, three times the maximum an adult would receive in hospital—to combat the extensive pulmonary edema caused by the salt water. The treatment worked.
Comex kept Lawson at saturation depth for several days to allow his condition to stabilize (against the advice of several hyperbaric specialists), with the diver medic who had ministered to him in attendance. They then began decompressing him. As he was decompressed, the pneumothorax—the pocket of gas outside the lungs—expanded, putting pressure on the lungs: a situation that was monitored with periodic x-rays. At about 30M/98', the pocket became unmanageable. A doctor locked into the chamber, and without an anesthetic inserted a needle in Lawson's chest and relieved the pneumothorax.
Lawson made a full recovery and returned to diving. Since the pneumothorax was not a result of weak spots in the lungs as in a spontaneous pneumothorax, there was no reason to disqualify him. For his extraordinary single-handed rescue Wiggins received the Frank Dearman Award of Merit, instituted by the AODC (of the UK) in 1980 to mark the memory of Frank Dearman OBE, one of the Association's founder members and a past chairman. Thanks to the ROV, the entire incident was recorded on videotape. The Department of Energy subsequently included the sequence in a safety video.
