Summary:
The session on Authority and Responsibility issues was wide ranging and included many examples of problems drawn from past experience. The workshop participants read over the current Section 15 of the UNOLS Shipboard Safety Standards and discussed its advantages and disadvantages. There was agreement that the Section 15 needs revision and that it could be a primary vehicle for creating a clearer definition of shipboard diving authority and responsibility. There was little controversy over the exact direction that a revision should take. It was felt that the current Section 15 of the UNOLS Shipboard Safety Standards should be revised to-
There were disparate opinions concerning the precise wording of the proposed revision. An ad hoc group undertook carrying these concepts forward into a full revision of Section 15. The subgroup's work was reviewed by the entire workshop, and it is recommended that it be forwarded to the RVOC for coordination within the RVOC of their revision of Section 15 of the Research Vessel Safety Standards. This revision would then go to UNOLS for final approval and promulgation. The text of the suggested revision follows shortly.
Additional observations, suggestions and questions included:
15: Diving Operations
15.0 Policy: Scientific diving is a normal part of oceanographic research vessel operations. Such diving conducted from a University National Ocean Laboratory System (UNOLS) vessel must be under the auspices of a diving program that meets the minimum American Academy of Underwater Sciences' (AAUS) Standards for Scientific Diving Certification and Operation of Scientific Diving Programs. Operators without a program may accommodate scientific diving cruises which are under the auspices of an institution with such a diving program.
15.1 Diving Procedures, Rules and Regulations: For all cruises a single lead institution's campus diving administration will be designated. This is usually accomplished by agreement of all campus diving administrations involved. Items which refer to the campus diving administration may, in fact, be the concern of the Diving Safety Officer according to the practices of the institutions involved. The procedures, rules and regulations that govern the diving operation are those of the designated lead institution, subject to the approval of the operator's Marine Office.
15.2 Cruise Planning: In a timely fashion prior to the cruise:
15.3 Cruise Personnel:
The simplest diving cruise is when the scientific party members are all from a single institution, and are going out on a ship operated by their home institution. It is increasingly the case that the science party includes participants from several institutions, including foreign institutions and institutions without formal diving programs. There may even be some volunteers or observers with no institutional affiliation. The ship may be operated by still another institution, which may or may not have a diving program or regulations appropriate to the scientific diving planned.
The procedure for handling these situations that has developed informally over the last few years works well. It was the consensus of the group that this should continue, as formalized in the revised texts of Section 15 of the UNOLS Shipboard Safety Standards (See Section above.) and Chapter 14 of the RVOC Safety Training Manual and are reflected in the proposed Pre-Cruise Dive Plan Form (Page 1 - Pre-Cruise dive Plan, Page 2 - Personnel, Page 3 - Equipment and Personnel Needs).
The roles in a multi-institutional diving cruise include the Project Principal Investigator, the cruise Chief Scientist, the On-Board Diving Supervisor, the science party members, the vessel Master, the research vessel operator and the campus diving administrations and Diving Safety Officers of all the institutions under whose auspices these individuals work.
The model process for planning a diving cruise involving all these parties is :
NOTE: CMAS is the acronym (in French) for the World Underwater Federation. This international organization has a Scientific Committee that issues an internationally recognized scientific diver certification based on a diver being a legitimate researcher and meeting a set of equivalencies of training and experience.
NOTE: Marine Superintendent' is used as generic term. The individual holding this position is referred to by different institutions (e.g., Port Captain, Marine Manager)
There may occasionally be situations that are not explicitly covered in this procedure, but the general mechanism of communication among the parties involved and final approval by the lead institution's campus diving administration should work in these cases as well.
The primary issue is whether or not adequate rules and guidelines presently exist in the UNOLS Shipboard Safety Standards, the RVOC Safety Training Manual, and/or the AAUS Standards for Scientific Diving Certification and Operation of Scientific Diving Programs covering the use by divers of small boats launched from research vessels.
Specific questions are:
Question 1: Are diving-related small boat standards needed?
The consensus is that rules and regulations exist, but these are not consistent or consolidated in one easy format. Most institutions have a manual with a section on small boats, normally outlining small boat operations, boat operator requirements, U.S. Coast Guard required equipment and safety procedures. These procedures often pertain to land-based operations and sometimes ignore small boats launched from larger vessels.
Most vessel operators have rules and regulations pertaining to small boat operations. These are written and unwritten, and are slightly different for each organization. There seems to be a wide range of procedures when it comes to scuba diving activities conducted from small boats launched from larger vessels either in the open oceans or in more protected areas.
The operators, at the workshop, recommend basic written standards pertaining to all small boat operations especially diving-related ones. In addition to these standards, each organization might have certain rules that only pertain to them or their operation.
Question 2: If so, what should these standards cover?
Small boat standards should cover all aspects of small boat operations including the following:
A) Operator Requirements
B) Operational Procedures
Question 3: What types of small craft are best for the diver/ship)?
Most operators and divers feel that the inflatable boat is the most suitable for scuba diving operations. The most desirable inflatable is the hard bottom version, which provide a very stable platform. In addition, inflatable boats can take a considerable amount of abuse when alongside the mother vessel. Many operators use small to medium size Boston Whaler-type boats to support diving operations. These boats are adequate in most cases, and many vessels carry two boats: one inflatable and one Boston Whaler-type. Research divers in cold waters may require a larger boat due to the bulky nature of their protective suits and the amount of lead needed to offset their suits' buoyancy.
Engine/drive designs are available that improve on the relative hazards of propellers, such as jet drives or a protective shroud around a regular propeller. These designs should be considered whenever a motor or boat is replaced.
Question 4: What qualifications should a boat operator have?
Reference Question 2. In addition, qualifications may be determined by operating organization.
Question 5: Should the boat operator be a crew member. a member of the science party, and/or a diver?
The majority of the time, the boat operator is a member of the ship's crew, and therefore the Master of the vessel is assured of his/her qualifications. If a member of the science party is designated as a small boat operator, he/she must be able to demonstrate small boat operator qualifications to the satisfaction of the vessel Master. It is desirable, but not required, that the boat operator be a diver. If the operator is a diver, participation in diving operations should not allow leaving the small boat unattended.
Conclusions:
There appear to be two distinct views concerning small boat activities: one is the vessel operator/Masters' point of view, the other the scientists/users' point of view. The Master's concerns are centered around the small boat operator's qualifications, whereas operators from the user's organization may be fully qualified, yet not possess a document stating so. The scientists/users in many cases are competent and qualified small boat operators having been trained by their own organizations. However, their requirements may or may not meet the ship operating organization's requirements. Some science groups furnish their own boats and operators while conducting science missions from another organization's vessel, and in most cases their members do not possess a document stating that they are qualified small boat operators. This leaves the Master in the position of having to decide whether or not to accept a verbal claim that a person is qualified.
UNOLS vessels routinely conduct small boat operations. Each organization should have rules and regulations in place, and while many are similar, none are the same. There is a need for a common set of rules that all organizations can either follow or use as guidelines to further supplement their own regulations. These basic guidelines should be incorporated into the UNOLS Shipboard Safety Standards and/or the RVOC Safety Training Manual.
The bulk of scientific diving experience is gained from operations in the near-shore environment involving small boats or shore-based diving. As was noted, 'Shipboard diving is quite different from small boat or shore-based operations and is, therefore, worthy of comments to aid the inexperienced'[7]. The protocol for diving operations from large oceanographic ships requires a higher level of skills and knowledge due to the more complex logistics and communication requirements and the increased safety margin necessitated by remote operations. This is true for both ship personnel and the scientific party.
The assumption that all members of such expeditions have been adequately trained and indoctrinated in the tasks to be performed may not always be valid because of ship or scientific party schedules. When it is perceived that personnel may not be qualified for the task to be performed, there is an added burden placed on the crew and operators of the vessels which may cause unnecessary workloads. Similar impacts are observed on the scientific party, who have not only the operational aspects to deal with but also the pressure of accomplishing the science.
Based on the collective experience of vessel Masters, Diving Safety Officers, and senior scientists,
the following areas of difficulty have been identified:
Evaluation of Basic Diver Skills
It is not uncommon for expeditions to include diving personnel from institutions other than the vessel operator. When such field efforts are planned, it is the responsibility of the Principal Investigator to assemble and review the participating divers' qualifications and proficiency level for the diving mode and task to be performed. This information is then forwarded to the lead institution's Diving Safety Officer for review and approval. At this point difficulties may arise from the use of different criteria for the evaluation of a divers' proficiency and skill.
The American Academy of Underwater Sciences sets forth standards for training and qualifying divers, and operating research diving safety programs [8]. Most of the UNOLS membership is active within AAUS, and UNOLS references in their own standards [9] the AAUS standards. AAUS standards cover basic diver training but do not directly address day-to-day shipboard scientific diving operations.
Research divers at AAUS Organizational Member institutions are provided with institutional 'diver certification cards' which indicate that their training corresponds to a consensual minimal level, that they have a current medical exam, and have maintained their skills by continuing their diving activity at or above a minimum defined level. The community's accident/incident experience demonstrates that AAUS standards are effective for shore-based scientific diving. It has always been the policy of AAUS that the specifics of the actual research diver training and qualification process, as well as the day-to-day operational procedures, are the responsibility of each diver's home institution. This provides the home institution with appropriate authority over its divers and allows each institution to ensure the skills and experience that are necessary to its diving operations and the particular environment in which their scientists are working. AAUS has sought to establish full reciprocity among institutions; however, there remain differences between the specific requirements and procedures of Organizational Members. This should not be viewed as negative, but simply as a reflection of how various institutions have approached specific problems in their operational environment.
It is often difficult for foreign divers and divers from institutions without an AAUS model research diving safety program to demonstrate (or document) their qualification for research diving cruises. Arrangements for the testing and certifying of such divers prior to a cruise involves either bringing the diver to a location where there is such a program or having the Diving Safety Officer (or a designated representative) travel to the diver's location. Both of these solutions can be expensive, time consuming and always raise the issue of who should pay for such services. An alternative is the inclusion of the Diving Safety Officer (or a designated representative) in the scientific party. This latter approach makes the researchers' ability to dive during the cruise uncertain (since the checkout dive does not occur until the start of the cruise), and may also be expensive in terms of funds (for travel and salary) and scientific berths.
The development of common policy approaches, criteria and evaluation protocols for the testing of the proficiency of shipboard scientific divers and support personnel is needed. This would alleviate the conflicts that sometimes occur between the visiting scientist and the host institution concerning both the evaluation of diver's proficiency for the task to be performed and the assignment of charges for such evaluations.
Evaluation of Operational Skills
As has been indicated above, diving operations from large oceanographic ships require additional skills for both ships' crew and scientific personnel. Logistics, communication and operations are generally more complicated for world-ranging vessels than for smaller coastal vessels. It is therefore imperative that all parties involved be versed and familiar with the tasks to be performed, and how those tasks will be accomplished. The initial measure of operational skill is most likely to be the submission of a complete and well formulated dive plan. This plan, submitted by the On-Board Diving Supervisor, must be reviewed with the vessel Master, as well as the Marine Office and Diving Safety Officer of the vessel-operating institution. Review of this plan can alleviate conflicts that sometimes arise due to differences in expectation between visiting scientists and the host institution with respect to operational protocols. Before diving operations begin, the Principal Investigator must meet with vessel crew who are expected to be directly involved with the operation, as well as with diving personnel, to review the dive plan and clarify lines of communication and authority. Emergency plans, which are an integral part of the dive plan, need to be reviewed and discussed at this time.
Development of New Training Standards
At present, the responsibility for establishing minimum training standards for scientific divers rests with AAUS. The implementation of these standards rests with the various campus diving administrations. When there is a call for a new diving procedure (and training for it), the steps often go this way:
A) A scientist identifies his or her need to dive under some special circumstance, with special gear and/or in a special way.
B) This scientist (and other researchers who want to use the technique) must convince his or her peers on the Diving Control Board that the use a new diving procedure is safe and warranted.
C) The researchers explore the ways other communities have used these procedures and, with the oversight of the campus Diving Control Board, either obtain training or develop new protocols.
D) As other researchers learn of the usefulness of the procedure, they convince their own Diving Control Boards of the need to use the procedures and the reasonableness of the way in which the procedures are currently in use at other institutions. At this time the procedures are often modified to adapt them to environmental conditions other than those for which they were developed.
E) If the use of these procedures spreads through the community, then the AAUS may hold a workshop or conference that results in a new community standard (See Appendix F:AAUS Guidelines for the Use of Diving Computers and Appendix G: AAUS Safe Ascent Recommendations); or
F) If the new technique is only of interest to a few divers or universities, then they will, with the campus Diving Control Board, evolve and use those protocols individually.
Summary
Use of well developed and accepted community standards result in confidence that the diving and support teams are qualified to perform the tasks required. The process of staging a diving cruise would be facilitated by the development of consensual evaluation and operational standards for diving from academic research vessels similar to that now in existence for small-boat and shorebased diving. Such standards should be developed by Organizational Members of the AAUS who represent a cross section of vessel operating institutions and diving scientists. A critical test of the success of such future standards is the acceptance of them by the research diving community as would be demonstrated by the evolution of a community expectation the all UNOLS institutions be Organizational Members of the AAUS.
Medical emergencies arising from injury are a long standing problem for persons at sea due to the remote location. Traditionally, ships are equipped with basic medical supplies and equipment to provide first aid and stabilization of victims prior to their transfer to the nearest appropriate medical facilities. Ship's traditional protocols for handling such emergencies are well established. However, in the event of a diving accident, where an individual may require recompression and specialized treatment, sources of aid and medical support are limited and require additional planning consideration.
Written requirements for diving emergency plans go back to the first diving safety manual developed at Scripps Institution of Oceanography [10] in the early 1950s. This document, and all similar subsequent documents, have required that emergency plans exist for all diving operations, ship-based or shore-based. As a result, diving cruises have a specific requirement for the preparation of an emergency plan, '...emergency plans which are acceptable to the lead DCB and to the operator's Marine Office must be prepared'. [11] This requirement for more than an ad hoc plan does not exist for non-diving cruises.
NOTE: 'DCB' is the acronym for 'Diving Control Board' which is the title usually applied to the campus diving administration.
Diving emergency plans are specifically designed to respond to a diving accident and generally require identifying and verifying:
A) Mechanisms for establishing communication links to medical advisory care (phone numbers and/or radio frequencies for medical advice, U.S. Coast Guard, foreign coast guards).
B) Evacuation contacts (phone numbers and/or radio frequencies for coast guards, navies) and working aircraft evacuation ranges for the operational area of the cruise.
C) In non-US waters, location of operating hyperbaric chambers and appropriate medical support.
D) Level of on-board medical assistance available/required (e.g., CPR, EMT).
The emergency plan represents a data source for specific information on regional sources of emergency medical support and transportation. While sources of such information are readily available within the waters of U.S., support services in remote areas are frequently lacking. At present, information on available facilities and support is compiled and accumulated by Principal Investigators and Diving Safety Officers of individual institutions and receives limited distribution. Such information is an important planning element for researchers involved in diving operations in remote areas, and for reference during operations in the event of a diving accident. Ship and research personnel should conservatively assume that they must be self-contained to respond to emergencies while working in remote areas.
Both facilities and support have to be integrated since the presence of shore-based recompression chamber facilities without medical support is of little use. As many evacuation options as possible should be documented. For example, within the service area of the U.S. Coast Guard, the U.S. Navy can also respond in certain situations as can various police departments. In addition, there may be private air ambulance services available. Medical information and support services such as MAS or Divers Alert Network (DAN) are available from the private sector, as well as the U.S. Coast Guard and U.S. Navy
NOTE: DAN is member-based public service organization headquartered at Duke University's F.G. Hall Hyperbaric Center. It sponsors conferences. distributes information and publications, and provides a free 24 hour hyperbaric medical consultation and referral service.
The driving issue centers first on a determination whether the diving operations represent a unique set of requirements to the safe operation of the vessel and the health of crew and scientific party. If there are unique requirements, then clearly unique plans need to be made.
Even when diving operations do not present unique or complex accident management problems, they do represent an additional layer of logistical concern since research divers, when submerged, are not in direct contact with surface personnel. In the event of an accident, the victim will require extraction from the water and transport to the support vessel. After transfer to the support vessel, the emergency protocol is not different from that required by other medical emergencies: provision of first responder aid, stabilization of the victim, communication with medical support and advisory services, preparation for evacuation, and transportation to medical treatment facilities.
Inasmuch as the direction of, and authority over, all diving operations lies with the On-Board Diving Supervisor, he or she must assemble the information and protocols that go into the Pre-cruise Dive Plan.
Emergency Plan File & Database
To assist Principal Investigators, On-Board Diving Supervisors, and ship personnel in the formulation of an emergency plan, it is proposed that a centrally located file consisting of past emergency plans be assembled and kept by geographic area. Part of this file would be a collection of response charts, each annotated with the location of evacuation facilities. The response charts would be scribed with 'response-radii' indicating the geographic areas that are within specific expected air evacuation response times. It is not intended that these charts serve as an 'off-the-shelf' product that is routinely maintained and up-to-date. Rather, these charts would serve as a starting point to be updated by the On-Board Diving Supervisor prior to a cruise in the area to be covered. The file's contents would be catalogued in an on-line computer database so that those responsible for preparing emergency plans would know what information was available as a starting point. This file would aid the determination of what facilities and support would be available and the general protocol to be followed in the event of a diving accident requiring hyperbaric treatment.
In practice, even the most well conceived plans are subject to a host of factors over which vessel operators and scientific staff have little or no control. Historically, it has not been uncommon to have evacuations take many hours due to sea and weather conditions when only a few hours were anticipated. Additionally, medical information and support is sometimes not immediately available. Such occurrences serve to illustrate the need for alternative plans to minimize delays which could be life threatening.
Portions of the database are already available. Some lie within resource documents of the Undersea & Hyperbaric and Medical Society [12], Divers Alert Network[13], and certainly within the research diving safety programs and marine offices of UNOLS institutions and AAUS Organizational Members. These materials could be collated at (and made available from) the UNOLS office. They should be updated whenever additional material was accumulated.
To provide an effective, readily available database, pre-printed entry forms should be developed and provided to UNOLS for distribution to Principal Investigators. Principal Investigators would complete and/or confirm the data during the Pre-Cruise Planning phase.
Summary:
The Emergency Plan Database is a file containing a list of facilities and support services available by region. It would be utilized by Principal Investigators, Diving Officers and ship personnel as an aid in emergency planning.
What is proposed is a long-term dynamic program, capable of growing and becoming more refined as data are accumulated and assimilated. The assembly of such a database would best be accomplished by a group familiar with and sensitive to the requirements of both the vessel operators and the scientific divers. A 'response-radius' chart should be required for all diving cruises as should the use of a form like the one above. The chart is filed by geographic area and the form is kept in an on-line database that could be queried by anyone putting together an emergency plan for a diving cruise
The basic question is whether or not recompression chambers should be required for UNOLS ships engaged in diving cruises.
Basic facts and assumptions which bear on the problem are:
A) Based on the track record of all of the UNOLS diving operations, bends resulting from ignoring time and depth limitations are unknown. One instance of an incapacitating over-pressure accident has been reported in this program.
B) Diving operations conducted at sea by commercial diving firms and military units have traditionally had recompression chambers present. These chambers' primary function is less to provide an emergency treatment facility, than to permit surface decompression. Surface decompression is a technique where the diver exits the water prior to the completion of his or her decompression obligation and is immediately re-pressurized in a chamber. The diver then decompresses as the chamber is brought to sea level pressure. Because of its dangers, this is not an approved procedure within the scientific diving community.
C) The desirability of a recompression chamber in treating a case of decompression sickness (DCS) is not questioned, although it may be possible to successfully treat simple Type I (pain only), and even some Type II (Central Nervous System involvement) bends with oxygen and other field methods without a chamber being used. This will be discussed below.
D) If a chamber is present on a UNOLS vessel, trained personnel also must be aboard to operate it and to be inside attendants. Divers with some college education or technical training can quickly be taught to operate a treatment chamber, and Emergency Medical Technicians (EMT), Diving Emergency Medical Technicians (DEMT), or Cardio-Pulmonary Resuscitation (CPR) trained personnel can be trained to function as inside tenders. All of this presupposes that adequate medical advice is available.
NOTE: The one incapacitating accident occurred in 1983. An analysis of this case reveals several contributing facts w should be noted:
A) The diver had been making repeated, multi-level, bounce dives ranging between 50 80 feet of sea water (fsw); he ran out of air and was forced to make a free, possibly uncontrolled ascent. He was diagnosed as having subcutaneous emphysema.
B) There was no breathing oxygen or mask on board the ship. As a result, welding oxygen was administered through a cutting torch, first using cupped hands to direct it to his face, then by a Styrofoam cup with the torch stuck through. It is doubtful if he received more than 50 percent oxygen at any time.
C) This diver had a previous history of air embolism in 1977 from which he made an apparently complete recovery without chamber treatment t. His authorization as a research diver was canceled by his home institution. After several years of petitioning and medical review, his diver status was restored.
D) The circumstances surrounding this (and the previous incident) raise the question of the presence of the existence of a patent foramen ovale, a heart condition involving a small hole between the atria. In divers this may permit venus blood, containing bubbles that normally would be filtered out by the lungs, to pass through into the arterial side. These bubbles then expand on ascent and create a blockage of blood supply referred to as an air embolism.
Most of the workshop participants feet that there is no reason to require the presence of a chamber on UNOLS diving cruises. This opinion is based on the thousands of open-ocean dives made by research divers with no decompression incidents. A small minority of workshop members stated that a chamber should be considered whenever diving is being undertaken.
If, as a result of an unusual cruise requirement, it were desirable to place a chamber on a UNOLS vessel, and provisions made for proper procedures and properly trained personnel, the following points relating to the type of facility need to be considered:
A) Multi-place chambers. There is no doubt that, from the standpoint of flexibility of treatment, a double-lock, multi-place chamber is preferable.
B) Mono-place chamber.
There are three items a Principal Investigator or Marine Superintendent should consider when deciding to place a chamber aboard a UNOLS vessel for a specific cruise:
A) Distance to a hyperbaric chamber: It must be constantly emphasized that diving has risks which the diver cannot avoid assuming. Having the best chamber and most qualified attendants immediately available cannot assure that the diver will not suffer serious or fatal consequences. Some neurological problems can become irreversible within a few minutes, and under such situations, even an immediately available chamber may not prevent serious consequences. No data exist which justify any specific permissible delay time for over-pressure injuries, Central Nervous System (CNS) or vestibular bends. Divers treated as long as several days after injury have made an apparently full recovery from Type 1. An arbitrary time of three hours has been set by some physicians as a permissible time for treatment delay. Other physicians feel that if air evacuation or some other means of transportation is not practical within six hours, the probability of successful treatment is diminished
B) Amount of Nitrogen Uptake: This is a function of the depth and length of dives as well as the frequency of diving. It is clear that the risk of bends is greater the deeper the diver goes, the longer he stays and the more frequently dives are conducted.
C) Risk of embolism: It is possible for a diver to embolize as a result of a breath-holding ascent from three feet to the surface in some circumstances. It is also possible that the diver may have a patent foramen ovale between the atria of the heart. Although a patent foramen ovale has been found in a large percentage of divers who have developed Type II bends, if a diver has a long history of diving without undeserved bends, many physicians feel it is unlikely that he or she has such an abnormality. A caution about this condition should be included in the diving waiver so that all divers are made aware of this newly detected problem and could have this checked if they felt it were a concern.
NOTE: Decompression injuries, also known as the 'bends' are divided into two different types:
1) 'Type One Bends,' which have no neurological symptoms, result from bubbles in skin capillaries or joints and typically cause a skin rash or joint pain; and
2) 'Type Two Bends' which are much more serious and result from bubbles effecting nerves or the organs of balance in the inner ear.
Prior to considering a chamber, thought should be given to other ways of providing a greater operational safety factor. The advantage is that these ideas are preventive rather than corrective. Several which should be considered are:
A) The use of in-water oxygen decompression. This is not in-water treatment of bends. This technique was used successfully in 1988 for over 3,000 safe two-a-day decompression dives to depths between 160 to 190 feet by the Department of Nautical Archaeology at Texas A & M University. Decompression tables for this technique were developed by Dr. Vann of Duke University. The present diving tables used by UNOLS (U.S. Navy or more conservative) are highly reliable. However, an additional safety factor would be obtained by using in-water oxygen at 20 fsw. The level of oxygen exposure in this procedure does not create a danger of oxygen toxicity. It might, however, justify an oxygen toxicity tolerance screening test on divers. The total cost of in-water oxygen decompression is far less than that of a recompression chamber.
B) Use NITROX breathing mixture in conjunction with air-based tables. This would cost more than simply using oxygen in the water, but is a viable breathing gas alternative. It would require some additional training, and any good diver could master it. It is clear that using an enriched oxygen mixture will not guarantee against bends, although tests have shown that it adds an extra safety factor if used with air tables at appropriate depths.
C) Screen all UNOLS divers for the presence of a patent foramen ovale as a part of their pre-diving physical examination. Such a screening can be done by some physicians. Here again, although the cost would be several hundred dollars, it might reduce the possibility of an unexplained case of bends. It should be pointed out, however, that probably many divers are diving successfully with a foramen ovale that is not sealed. One physician who discussed this is of the opinion that the data so far available do not warrant wide screening of divers.
D) Train personnel to be able to administer intravenous liquids such as Dextran. Research at Texas A & M University demonstrated that, in most instances, doppler detectable bubbles in goats with bends were reduced and even disappeared. This idea needs to be studied further on humans.
Conclusions:
Careful analysis of more then 40 years of research diving efforts does not, at this time, indicate a safety problem that dictates either a requirement for the installation of a chamber on a UNOLS vessel that is conducting a diving cruise or the use of the methods of increasing safety margins that are detailed above. Given the excellent past record and careful nature of UNOLS diving, it is unlikely that a requirement for a chamber will be warranted in the future. However, data on the question of appropriate safety margins should continue to be collected and reviewed.
Recommended Actions:
There are three categories of recommendations:
A) Chamber requirements: In view of the past UNOLS experience, no chamber should be required for diving cruises. However, a chart of all bodies of water contiguous to the U.S., identifying the location of available shore-based treatment chambers, together with information on the availability of evacuation equipment, and reaction time for emergency evacuation should be prepared and reviewed to determine possible evacuation timing.
B) Promotion of diving procedures that would further increase diving safety:
C) Encourage future research aimed at:
Endnotes:
7 'Shipboard Diving Procedures,' Stewart, J. R.: 1971, in Part III of 'The Scripps Institution of Oceanography Marine Technicians Handbook,' Institute of Marine Resources, La Jolla, CA. - Included in this report as Appendix E.
8 'Standards for Scientific Diving Certification and the Operation of Scientific Diving Programs,' Heine, J. (Chairman): 1989, American Academy of Underwater Sciences, Costa Mesa, CA.
9 'UNOLS Shipboard Safety Standards,' Section 15: 1889, University National Oceanographic Laboratory System, University of Washington, Seattle WA.
10 'The University Guide for Diving Safety', University Conference of Environmental Health and Safety Officers: 1967, University of California, Berkeley, CA.
11 'UNOLS Shipboard Safety Standards,' Section 15: 1989 University National Oceanographic Laboratory System, Seattle, WA.
12 'Hyperbaric Chambers in the United States and Canada' Batz, P. G. & Myers, R. A. M. (Eds): 1990, Undersea and Hyperbaric Medical Society, Bethesda, MD.
13 'The DAN Underwater Diving Accident Manual, Revised Edition,' Mebane, G.Y. & Dick, A.P.: 1985, Divers Alert Network, Duke University, Durham, NC.