JINDO, South Korea, May 2 (Yonhap) -- Divers participating in the search of a sunken ferry face growing health risks from swimming in cold, murky waters for extended stretches, with several suffering from decompression sickness, officials said Friday.
Hundreds of Coast Guard, Navy and civilian divers have battled strong currents and high tides to bring a steady flow of bodies from the upturned ferry Sewol that sank in waters off the southwestern island of Jindo on April 16.
The confirmed death toll has risen to 226 and 76 still remain missing, with many of them believed to be trapped inside the ship.
The search and rescue operation has long since turned into a grueling recovery of corpses as no one has been found alive since the day of the ship's sinking. The work has been becoming even more difficult as divers have had to break through closed cabin doors blocked by debris.
As search efforts continued round-the-clock over the past several days amid growing pressure from grieving families, divers have increasingly suffered exhaustion, with some of them treated for decompression sickness after ascending from depths of over 30 meters.
On Thursday, a 31-year-old civilian diver fell unconscious after diving four times before daybreak to set guideline ropes around the ship, raising concern over the safety of divers.
He received treatment at a hyperbaric oxygen therapy center, but continued to complain of a severe headache and pains in his pelvis, typical symptoms of decompression sickness, according to hospital officials.
Decompression sickness is a painful and potentially dangerous condition that strikes deep sea divers who surface too quickly or stay in cold waters for a long time, causing paralysis, vomiting, and aching pains in joints, the ears and other parts of the body.
"For the first time in my 20 years of a diving career, I was seized by fear that I might not be able to return from underwater," a senior diver told Yonhap News after his colleague fell unconscious.
So far, dozens of divers have received treatment in the oxygen chamber that provides patients with pure oxygen in a sealed chamber that has been pressurized above normal atmospheric pressure.
As the search is expected to last throughout next week, the government disaster response team limited each diver to swimming only once a day to prevent decompression sickness.
The work is still tough as the difference between high and low tide is the highest at the disaster site during this time of year. Currents are stronger by about 40 percent during spring tides compared with the period of neap tides when the difference is the smallest.
"I become exhausted even after one diving a day due to strong currents and deep diving," another civilian diver said. "Figuratively speaking, it's like riding a roller coaster for dozens of minutes or up to one hour."
Families have also raised concern that rescue workers may not be able to retrieve all bodies from the upturned ship as several bodies have recently been retrieved from waters far from the disaster site.
One body, believed to be that of a female student, was found about 4 kilometers southeast of the disaster site. The location was in the opposite direction from a site where another body was recovered two days ago.
The government disaster response team has set up multiple nets around the area to prevent bodies from being swept away by strong currents, officials said.
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