The British Sub-Aqua Club NDC Diving Incidents Report 2004 Compiled by Brian Cumming Diving Safety and Incidents Advisor Published by The British Sub-Aqua Club in the interests of diving safety ` NDC Diving Incidents Report - 2004 Introduction This booklet contains the 2004 Diving Incidents Report, produced by The British Sub-Aqua Club (BSAC) in the interest of promoting diving safety. It is important to note that it contains details of UK diving incidents occurring to divers of all affiliations, plus incidents occurring worldwide involving BSAC members. Report Format The majority of statistical information contained within this report is also shown in graphical form. Please note that all statistical information is produced from UK data only and does not include Overseas Incidents unless noted as ‘All Incidents’. The contents of this report are split into an overview of the year, and then the details of nine incident categories plus some historical analyses. The various sections can be found as shown below:- i) Overview Page 1 ii) Fatalities Page 5 iii) Decompression Incidents Page 8 iv) Injury / illness Page 18 v) Boating & Surface Incidents Page 24 vi) Ascent Problems Page 30 vii) Technique Problems Page 38 viii) Equipment Problems Page 40 ix) Miscellaneous Incidents Page 42 x) Overseas Incidents Page 43 xi) Numerical & Statistical Analyses Page 46 xii) List of Abbreviations Page 48 Within each category the incidents are listed in the order of their occurrence, not necessarily that of Incident Reference. They are laid out in the following form: MONTH/YEAR OF INCIDENT INCIDENT REF. Brief Narrative of Incident.................................................................................... ........................................................................................................ The nature of many diving incidents is such that there is usually more than one cause or effect. Where this is the case the incident has been classified under the more appropriate cause or effect. For instance an incident involving a fast ascent, causing decompression illness, will be classified under 'Decompression Incidents'. Brian Cumming, BSAC Diving Incidents Advisor, November 2004 Acknowledgements Data for this report are collected from several different sources. I would like to extend my thanks and appreciation to the following for their assistance in its production and in ensuring its completeness: Ken Bazely, National Diving Liaison Officer, HM Coastguard Peter Chennell, Sea Safety Manager, Derek Scrivener, Service Information Data Quality Supervisor, Roger Aldham, Data and Statistical Analyst, Royal National Lifeboat Institution and, in particular, all of those divers and other sources who have taken the trouble to complete Incident Reports and share their learning experience with others. Finally, to Dr. Yvonne Couch for proof reading this report NDC Diving Incidents Report - 2004 Overview has seen an increase in the number of incidents A worrying trend is the increase in the number of incidents in 2004 reported. This reverses the situation reported the 'Ascent' category, which has increased by 50% over the last year where a significant drop in reported average of the last six years. This group of incidents relates to incidents occurred. The following chart shows the pattern over incorrect ascent procedure where no subsequent problem the last 14 years. The downward trend seen in 2002 and 2003 arose. Many rapid ascents result in a DCI and as such would has not continued. In the previous decade the number of be placed in the 'DCI' category. reported incidents increased by about 20 per year; it is possible Typically a diver loses control of his or her buoyancy during the that we are now seeing a levelling off at around 400 per year. ascent and makes an uncontrolled ascent to the surface, often missing decompression stops. Typical reasons are distraction Number of reported incidents whilst deploying a delayed surface marker buoy, jamming of the delayed SMB reel and lack of skill with drysuit buoyancy control. 500 All of these are avoidable by the use of correct techniques, good training, sufficient practice and correct equipment maintenance. 400 Categorisation of the year’s incidents 300 200 DCI 100 Boat / surface Ascents 0 Injury / Illness 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 Fatalities Equipment Incident year Miscellaneous Technique The distribution of reported incidents is shown in the following Overseas chart. As can be seen, 69% of these incidents have occurred in the summer period. This is totally consistent with previous 0 20 40 60 80 100 120 140 years, reflecting the increased number of dives that take place Number of incidents during the warmer weather. There is a slight and unusual dip in June, but this probably reflects the weather conditions during that month. Fatalities Monthly breakdown of all incidents - 2004 The 2004 incident year has seen 25 fatal incidents in the UK, a serious increase compared with the average of 16.5 per year over the last ten years. 6 of the 25 were BSAC members. 80 70 The factors associated with these fatalities can be summarised 60 as follows:- 50 • Five cases involved people who suffered a serious medical 40 problem (typically a heart attack) whilst they were diving. 30 This is a high number compared with an average of two per 20 year over the previous six years. 10 • Eight cases involved divers who were, or who became, 0 negatively buoyant and sank. In a number of cases divers were at the surface, in difficulties, but were unable to Sept. Aug. July June May Apr. remain at the surface. In other cases divers were in Mar. Feb. Dec. difficulties and ascending, when they started to sink back Nov. Jan. '04 down. These divers were all close to safety but buoyancy Oct. '03 Oct. issues took them away from the surface and they lost their lives. The average of such instances over the previous six years is 2 per year, and hence this year's events represent Incidents by category a substantial increase. This is an area that we need to The incident database categorises all incidents into one of nine emphasize in our training programmes. Divers must be major categories, and the following chart shows the distribution able to make themselves positively buoyant easily and of the 2004 incidents into those categories. quickly, so that their automatic response as soon as a The highest number of incidents relates to ‘Decompression problem of this nature starts to develop is to inflate a Illness (DCI)' and this is consistent with previous years. buoyancy device and/or dump weights. If they are 'Boating and Surface' incidents are the second largest category underwater at the time, the resultant ascent may cause its and the 2004 numbers continue the previously identified trend own problems but it is likely to be far less serious than the of a steady decline in this type of incident. More reliable and alternative. better-serviced engines and divers taking more care to ensure • Six cases involved separation. that they don't become lost are at the heart of this improvement. In each of these cases the separation was not planned. ©BSAC - 2004 1 ` NDC Diving Incidents Report - 2004 Two cases involved a diver who became separated during conclusion that some dramatic change must have taken place the descent. In one case it was a trio diving and in another to cause this increase. it was two pairs together. Two cases involved divers who became separated during the course of a dive; one of these cases involved a trio. Incident depths One case involved a trio ascending, and, while two of them The following chart shows the maximum depth of the dives were resolving a line tangle, the third diver was lost. during which incidents took place categorised into depth range The final case involved a diver who was sinking quickly and groupings. his buddy was unable to stay with him. • Five cases involved groups of three divers diving together (trios). Three of these involved separation, as highlighted Maximum depth of dive involving an incident above. • Four cases involved equipment issues. One case involved a cylinder that was turned off. Unknown One case involved a rebreather that was not set up correctly before the dive. Surf. One case involved a BCD that the diver was not familiar 1-10m with. In the fourth case the specific issue was not made clear. 11-20m • Four cases involved divers diving deeper than 50m. 21-30m One involved a diver at 58m breathing air. 31-40m One involved a diver whose body was found at a depth of 41-50m 67m. The last case involved a double fatality where the divers' 51-60m bodies were found at 70m. >60m • Three cases involved divers running out of breathing gas. In one case this was as the result of an entanglement and 0 20 40 60 80 100 120 140 160 180 associated problems. Number of incidents In one case it was the primary cause of the incident. The pattern of depths in the 0m to 50m range is very similar to In the last case it would appear that a diver accidentally that normally seen and reflects the amount of diving that takes used his pony cylinder regulator at the start of the dive and place in these depth ranges. The number of incidents reported problems arose when this cylinder unexpectedly ran out. in the greater than 50m range is 14, which is in line with • Two cases involved rebreathers. previous years. However 4 of these 14 were fatal incidents, clearly indicating the risks associated with deep diving. Often multiple causes were involved in an incident and in thirteen of these fatal incidents there is insufficient information The BSAC advises that no air dive should be deeper than 50m, available to be clear about the exact chain of events and root and that dives to 50m should only be conducted by divers who causes.