SKIN-DIVING BY AMATEURS

Press, Volume XCVIII, Issue 28894, 14 May 1959, Page 12

SKIN-DIVING BY AMATEURS

Warning Given On Aqualungs “The Press” Special Service AUCKLAND, May 13. The danger of amateur skindivers using war-surplus equipment to make their own aqualungs was emphasised by Mr J. E. Hansen in a paper read to a symposium on the use of compressed air in industry at Seddon Memorial Technical College. “A cylinder of air with 2400 pounds a square inch pressure in it, with a diameter of six inches, has a total pressure of 34.8 tons on its end,” he said. “The cylinder is under considerable strain and any metal fatigue or weakening brought about by water in the cylinder can lead to disastrous results. “When compressed air was being used for underwater breathing it must be pure and must be made in the correct type of compressors,” said Mr Hansen. Filters Needed Filters and separators had to be used to remove all traces of water, oil and particles from the air a diver would breathe. “Letting just a little bit of carbon monoxide into the cylinder is like planning to be just a little bit dead,” he said. Modern aqualung cylinders with a capacity for pressures up to 3000 pounds a square inch were tested up to one and a half times that pressure, but they should also be retested hydraulically at least every two years. Many amateurs adapted Air Force surplus carbon dioxide bottles for their aqualungs. There had been cases—fortunately when no-one was near—where the cylinders had exploded like small bombs. The latest underwater bottles were made of high-tensile steel cylinders with special linings to prevent corrosion.

Cadet Corps Officers.—Secondary school cadet corps officers now at Burnham Military Camp are undergoing different courses for Confirmation of their commissions and promotions to the ranks of captain and major. The officers are teachers and come from several South Island centres.