SAFETY PRECAUTIONS-cont.

iv U.S. Navy Diving Manual WARNING Hyperventilation is dangerous and can lead to unconsciousness and death. (Page 3-20) WARNING Never do a forceful Valsalva maneuver during descent or ascent. During descent, this action can result in alternobaric vertigo or a round or oval window rupture. During ascent, this action can result in a pulmonary overinflation syndrome. (Page 3-23) WARNING Do not use a malfunctioning compressor to pump diver’s breathing air or charge diver's air storage flasks as this may result in contamination of the diver's air supply. (Page 4-11) WARNING Welding or cutting torches may cause an explosion on penetration of gas-filled compartments, resulting in serious injury or death. (Page 6-22) WARNING Scuba equipment is not authorized for use in enclosed space diving. (Page 6-25) WARNING Skip-breathing may lead to hypercapnia and shall not be practiced. (Page 7-30) WARNING During ascent, the diver without the mouthpiece must exhale to offset the effect of decreasing pressure on the lungs which could cause an air embolism. (Page 7-36) WARNING During enclosed space diving, all divers shall be outfitted with MK 21 MOD 1 with EGS or MK 20 MOD 0 that includes a diver-to-diver and diver- to-topside communications system and an EGS for the diver inside the space. (Page 8-30) WARNING For submarine ballast tanks, the divers shall not remove their diving equipment until the atmosphere has been flushed twice with air from a compressed air source meeting the requirements of Chapter 4, or the submarine L.P. blower, and tests confirm that the atmosphere is safe for breathing. Tests of the air in the enclosed space shall be conducted hourly. Testing shall be done in accordance with NSTM 074, Volume 3, Gas Free Engineering (S9086-CH-STM-030/CH-074) for forces afloat, and NAVSEA S-6470-AA-SAF-010 for shore-based facilities. If the divers smell any unusual odors they shall immediately don their EGS. (Page 8- 30) WARNING If the diving equipment should fail, the diver shall immediately switch to the EGS and abort the dive. (Page 8-31) WARNING If job conditions call for using a steel cable or a chain as a descent line, the Diving Officer must approve such use. (Page 8-33) WARNING Altitudes above 10,000 feet impose a serious stress on the body and significant medical problems may develop while the acclimatization process takes place. Ascents to these altitudes must be slow to allow