Diving Safety Lines 4th Quarter 2000 1. Mk 16 Near Mishap 2. Master Diver's Corner 3. Cold Water Diving 4. Diving Statistics 5. Back Injuries Aren't a Matter of Fitness 6. Hail and Farewell 1. Mk 16 Near Mishap A Mk 16 diver fails to notice the flashing red light of his primary display indicating he has a low oxygen partial pressure. Instead of manually adding oxygen to the breathing loop and terminating the mission (as required by Mk 16 emergency procedures), the diver continues the dive. He eventually succumbs to hypoxia and drowns. That scene occurred over five years ago in the last operational diving fatality in the Navy. It almost happened again in October. Five years ago, the diver was so focused on his hand-held sonar that he didn't notice the flashing red light. In October, the diver did not have the primary display affixed to the Mk 16 mask. Instead, it was attached to the diver's wrist and covered with a Velcro wrist strap. Frequent monitoring of the Mk 16 primary and secondary displays might have prevented this near mishap, but the diver did not look at his displays as often as required, for obvious reasons. Additionally, the diver was conducting the dive alone and untended. A post-incident investigation revealed loose cable connections between the primary electronics assembly and the oxygen add valve. This type of equipment malfunction allows water intrusion into cable connector assemblies and is an indicative factor for low oxygen partial pressure readings. Here are some other lessons learned as a result of the near mishap: - The case of hypoxia was attributed to a failure to follow established operating and emergency procedures for the Mk 16. Although the possibility of water intrusion into the Mk 16 electronics is a known problem with the rig, frequent monitoring of primary and secondary displays and proper emergency procedures for the indications of water intrusion will negate the chances of hypoxia. - The near fatality was caused by a failure to follow safe diving practices. The diver did not have a buddy and was not tended by topside. Untended, single diver operations are not authorized in the U.S. Navy Diving Manual except under extreme conditions. That criterion was not met; this was a training dive, not an "extreme condition." - Pre-dive briefs should emphasize the symptoms of hypoxia as well as other diving-related maladies and the importance of following standard diving emergency procedures. The diver continued the dive despite being "air hungry" when entering the water. The diver should have let someone know the rig was malfunctioning. In response to this incident, Program Executive Office Mine and Undersea Warfare (PEO-MUW) has released a Mk 16 UBA advisory (DTG 080702Z NOV 00) that provides additional guidance for pre-mission and pre-dive checks of the cable connector assemblies into the scrubber, cable connector, or primary electronic assemblies. In addition, diving advisory 00-10 (DTG 240635Z NOV 00) reiterates the lessons learned above. If you are using the Mk 16 UBA, make certain you check the water-block connectors prior to the dive and follow proper diving procedures. Remember the golden rule of diving: Plan your dive and dive your plan. POC: BMC(SW/DV) Vitez, Ext. 7087 rvitez@safetycenter.navy.mil 2. Master Diver's Corner This is for the submarine scuba divers. Over the past few months, we have been providing diving assistance with submarine safety surveys. In some cases, what we have discovered is distressing. Listed below are the most common discrepancies we have seen. a. Equipment is not stowed properly (e.g., scuba regulators and buoyancy compensators wadded up and stuffed into a very small locker). b. Revision 4 of the U.S. Navy Diving Manual is not being used, or the most recent changes are not entered in the manual. c. Current messages to AIG 239 are not kept or posted where all divers have access to them. d. CPR qualifications have lapsed. e. Regulator over-bottom pressure is set incorrectly. f. Technical manuals are either not available or in such poor condition that they are no longer usable. g. Gauges are out of calibration. h. Equipment maintenance is not entered properly in PMS. i. Diver training is not conducted regularly. j. Diving requalifications are not entered in personnel folders. We understand that being a submarine scuba diver is a collateral duty, however, that is not an excuse for inattention to detail. I strongly recommend you take a good look at your diving lockers--what you find might surprise you. If your locker has some or all of the aforementioned problems, you are setting yourself up for a diving mishap. Correct the discrepancies and check your program often; it will make things safer for your divers. If you need any help, please don't hesitate to contact us. POC: HTCM(DSW/SW/MDV) Matteoni, Ext. 7082 lmatteoni@safetycenter.navy.mil 3. Cold Water Diving With the winter months fast approaching, it's time to get reacquainted with Chapters 6, 7, and 11 of the U.S. Navy Diving Manual (Revision 4). These chapters contain information you need to consider when planning dives under or near ice-covered waters at or below 37 degrees Fahrenheit. Remember, proper planning is an integral part of identifying and assessing hazards in the operational risk management (ORM) process. Listed below are some of the safety issues you should take into account before you begin your next cold water dive: - Review the task and requirement for ice diving to determine if it is operationally essential. - Determine the following environmental conditions: water temperature and depth of the water, ice thickness, wind velocity, current, visibility, and light conditions. Ideally, the diving supervisor or someone with ice-covered or cold water diving experience should survey the proposed dive site. - Choose the type of dive equipment best suited for the operation. - Consider logistics such as transportation, ancillary equipment, provisions, fuel, tools, clothing and bedding, medical evacuation procedures, and communications equipment. - Train all divers to be alert for hypothermia. The signs and symptoms of dropping core temperatures are given in Table 3-1 of the diving manual. Immersion hypothermia is a potential hazard whenever diving in cool or cold waters. A diver's response to immersion in cold water depends on the thermal protection worn and the water temperature. You can prevent hypothermia by selecting the appropriate diving suit (e.g., wet suit, dry suit, and hot water suit) considering both the water temperature and the planned duration of the dive. Less insulation improves the diver's dexterity and ability to swim, but also contributes to a greater loss of body heat and increases the risk of hypothermia. Adequate thermal support of divers and topside personnel is a necessity if operations are to proceed safely. POC: BMC(SW/DV) Vitez, Ext. 7087 rvitez@safetycenter.navy.mil 4. Diving Statistics Here are some of the latest statistics on diving within the Department of Defense. These charts show the breakdown by dive purpose and dive apparatus for calendar years 1997 through 2000 (data through 30 September 2000). DIVE PURPOSE 1997 1998 1999 2000* 4 year total SPEC WAR OPS 11688 10204 13451 5775 41118 REQUAL 3914 4846 6407 2922 18089 SEARCH 1988 2909 3882 1678 10457 RESEARCH 2994 1855 2661 1618 9128 SALVAGE 615 1558 873 223 3269 SELECTION PRESSURE TEST 339 171 156 151 817 STUDENT TRAINING DIVE 7665 14251 15362 15958 53236 INSIDE TENDER HUMANITARIAN TREATMENT 166 176 172 173 687 INSTRUCTOR SAFETY OBSERVER 2955 2854 2626 1534 9969 INSIDE TENDER PRESSURE TEST 428 315 192 147 1082 SECURITY SWIM 391 290 160 105 946 UNDERWATER CONST OPS 2241 2269 3328 82 7920 OTHER 707 1272 1626 1055 4660 INDOCTRINATION 129 302 277 189 897 INSPECTION 2743 1969 1884 1302 7898 SHIPS HUSBANDRY/REPAIR 14711 14618 10105 7346 46780 RECOVERY 711 857 470 134 2172 INSIDE TENDER RECOMPRESSION TREATMENT 213 236 251 93 793 INSIDE TENDER CLINICAL HYPERBARIC TREATMENT 703 977 572 528 2780 EOD OPS 6692 6934 7234 4189 25049 INSIDE TENDER AV BENDS 38 39 31 31 139 ICE DIVING 0 13 155 35 203 AIDS TO NAVIGATION 0 29 18 21 68 Totals per year 62031 68944 71893 45289 248157 *Through 30 Sep 00 DIVE APPARATUS 1997 1998 1999 2000* 4 year total SCUBA OPEN 27757 30626 30497 20228 109108 CHAMBER 3033 3109 2557 1928 10627 LAR-5 11350 10785 19101 9137 50373 NONE (FREE ASCENT) 9 0 53 100 162 FFM SCUBA 178 257 257 248 940 MK-20 9719 10213 8509 6461 34902 MK-21 MOD O 2044 3310 1360 1216 7930 MK-21 MOD 1 5024 6919 5749 3097 20789 MK-16 2390 3017 3022 1980 10409 EXPERIMENTAL 525 695 744 890 2854 MK-22 2 13 40 4 59 SUPERLITE 17B 0 0 4 0 4 Totals per year 62031 68944 71893 45289 248157 *Through 30 Sep 00 If there are other specific statistics that you or your command needs to have, please contact us with the details. We will attempt to retrieve the data for you as fast and as accurately as possible. POC: MMC(SS/DV) Gest, Ext. 7103 kgest@safetycenter.navy.mil 5. Back Injuries Aren't a Matter of Fitness A diver attempts to pick up a pair of scuba bottles. Not bending at the knees, he feels a sharp pain in his lower back. Quickly, he stops lifting and lies down to ease the pain until corpsmen arrive and move him to medical for evaluation. The diver has to take medication and loses two workdays because of his back pain. This shipmate is one of many who, although in top physical condition, suffers from back ailments. Why do we have all these problems? The answer, I feel, lies in what we do as divers. Preventing back injury is easier than correcting it. Accordingly, we need to pay attention during those sessions of back-injury-prevention training we receive upon reporting to a command and at least annually thereafter (see OPNAVINST 5100.19C, with change 2, paragraph A0406, for complete guidance). Additionally, we need to apply the five-step operational risk management (ORM) process to our jobs. For instance, when we're assigned to load out diving equipment on board a ship, we should apply ORM like this: Identify hazards: Know your limits and recognize the obstacles ahead of time. Assess the hazards: Use the risk-assessment matrix. Make risk decisions: Reduce the lifting load. Wear back braces if prescribed by medical authority, use conveyors, and ask for help. Weigh the benefits against the cost. Implement controls: Hold a safety brief and post or coordinate safety procedures from OPNAVINST 5100.19C, with change 2, to minimize the identified hazards. Supervise: Ensure your controls are effective, and watch for change. For more information about the ORM process, refer to OPNAVINST 3500.39 (Operational Risk Management). POC: HMC(SW/DV) Keltner, Ext. 7118 tkeltner@safetycenter.navy.mil 6. Hail and Farewell This quarter, we're welcoming aboard our new master diver, HTCM(DSW/SW) Hinkebein. MDV Hinkebein comes to us from Trident Refit Facility King's Bay, Georgia. He will be replacing HTCM(DSW/SW) Matteoni who is moving on to SEAL Delivery Vehicle Team TWO in Little Creek, Virginia. CDR Sutton is also leaving us this quarter. He will be transferring to Fleet Information Warfare Center in Little Creek, Virginia. We wish them both "fair winds and following seas." 8 7