Diving operations, simple or complex, require adherence to proven diving procedures. These procedures have been established after countless hours of diving experience in many diving environments. To ensure safe and efficient diving operations, all diving personnel should have a thorough understanding of the procedures presented in this section. This must be reinforced with local procedures, familiarity with the area, and regulations dealing with the immediate situation. Poor procedures not only result in unnecessary and costly delays, but also affect the success of a project and increase susceptibility to accidents.

6.1 PLANNING THE DIVING OPERATION 6.1.1 Definition of Mission and Goals

A clear definition of the mission and its goals is an imperative first step in planning a diving operation. Diving procedures, selected in consonance with the mission and goals, are of primary importance in successful underwater projects.

In establishing an operational plan all parties engaged in the project should participate, including those who will be actively diving as well as those engaged in nondiving roles. The role diving will play in the overall project should be defined. Resources, including qualified divers, diving equipment, surface or underwater support platforms, and support equipment must be determined. Logistics to get the diving operation to a site on time at a minimum cost must be assigned. A clear definition of the goals to be achieved and the responsibility of the divers must be specified. The data or samples to be gathered, work to be performed, or observations to be made, must be determined, and bottom time to achieve these goals estimated as closely as possible.

Also, the instrumentation, equipment, and underwater techniques to be used to accomplish the goals must be decided upon.

As in all endeavors, the defined missions and goals of a diving operation must be regularly examined and, as required, updated and altered to reflect the oftentimes changing tone of a project.

6.1.2 Selection of Diving Equipment

Selection of the type of equipment best suited for a diving operation is dependent, generally, upon the environmental conditions to be encountered at the dive site, as well as the dive's mission and goals. More specifically, the equipment must:

1. Allow the diver to ascend and descend in the underwater environment safely and in relative comfort.

2. Allow the diver the ability to accomplish required tasks.

Divers will use, during the majority of their diving operations, one of the following types of diving equipment systems:

Open-Circuit Scuba (Figure 6-1)

■ Umbilical-Supplied Systems (Figure 6-2) ■Closed-Circuit Scuba (Figure 6-3)

The majority of dives conducted by divers will be to depths of 130 feet and less, using opencircuit air scuba. However, because of the variety of environmental conditions that divers encounter, and the varying mission requirements imposed by different projects, other types of diving equipment may be required and must be considered. Depth and duration of the dive; type of work to be accomplished (heavy work, light work, silent work); temperature of the water; amount of current at the dive site; all these influence the selection of diving equipment. Detailed descriptions of the various types of diving equipment are given in Section 4. For plan

Major Advantages

Heat can be supplied for suit and breathing medium

Not limited by breathing medium supply duration

Voice communication

Not limited to air as the breathing medium Major Disadvantages

Limited mobility

Significant support requirements

Closed-Circuit Scuba

Generally Used For

Missions requiring quiet, long duration observations

Major Advantages

Mixed gas capability

Noiseless operation

Conservation of breathing medium
Long duration

Major Disadvantages

Complicated maintenance.

Extensive diver training requirements
Lack of efficient voice communication.

6.1.3 Dive Team Organization 6.1.3.1 Dive Master

The selection of personnel for a diving operation begins with the selection of the Dive Master. Total responsibility for safe and efficient conduct of the diving operation rests with the Dive Master. He must be an experienced diver, qualified to at least the requirements of the proposed dive. Once designated, he is the only person in charge of the diving operation. No diving will be conducted when he is not on the scene. The Dive Master's responsibilities are many and include, but may not be limited to, the following:

1. Overall charge of the diving operation

2. Safe execution of all diving

3. Preparation of a basic plan of operations. 4. Liaison with other organizations

5. Determination and selection of equipment 6. Proper maintenance, repair, and stowage of equipment

7. Selection, evaluation, and briefing of divers and other personnel

8. Monitoring the progress of the operation and updating requirements as necessary

9. Tabulation and submission of results and required records

10. Monitoring of decompression (when required). The Dive Master is responsible for the assignment of all divers to an operation and for ensuring that their qualifications are equal to or exceed the requirements of the dive. The Dive Master shall ensure that all divers are thoroughly briefed as to the missions and goals of the operation. Individual responsibilities will be assigned each diver by the Dive Master. Where special tools or techniques are being used, the Dive Master shall ensure that each diver is familiar with their application and use. Practice and refresher dives shall be made as necessary to ensure safe and efficient operations at the designated dive site. Although the Dive Master must be a knowledgeable diver, it is recommended that in operations involving a large number of divers or very complex dives the Dive Master perform no actual diving but devote his entire time to directing the operations of other divers.

6.1.3.2 Diving Medical Officer/Medical Technician

The advantage of a qualified Diving Medical Officer on site cannot be discounted. It is recognized however, that this may not always be practical. A Dive Master should not discount the possibility of obtaining a Diving Physician for the program, particularly if the operation will be at some distance from emergency assistance; if any decompression diving is planned; or if the operation involves a large number of divers and dives.

As an alternative to a Diving Medical Officer, a Diving Medical Technician should be considered for major programs. The technician, although not a physician, is experienced in determining divingrelated accidents, and, under the direct advice of a physician, administering temporary first aid until the services of a physician can be reached. Most Diving Medical Technicians are also qualified chamber operators.

If a Diving Medical Officer or a Diving Medical Technician cannot be obtained for full time onsite assistance, the Dive Master should consider the use of a medical officer on shore who is on 24hour-a-day call throughout the operation. Should an emergency arise, the medical officer can be in direct radio contact with the ship and provide Consultation.

6.1.3.3 Science Coordinator

On missions where diving is performed in support of scientific programs, a Science Coordinator should be designated. The Science Coordinator is the prime point of contact in the operation for all scientific aspects of the program. Scientific equipment, its use, calibration, and maintenance. fall under his purview. Working with the Dive Master, the Science Coordinator briefs divers on upcoming missions, and supervises the debriefing and sample or data accumulation following a dive.

6.1.3.4 Divers

Although the Dive Master is ultimately responsible for the overall diving operation, each individual diver has his own responsibilities. He is responsible for maintaining himself in proper physical condition and for the checkout of his equipment prior to a dive. He must ensure that he thoroughly understands the tasks(s) he is going to perform prior to entering the water. He is required to obey all signals from the surface. Finally, he is responsible for the successful completion of his assigned tasks.

6.1.3.5 Support Divers and Other Support Personnel

In most diving operations the number and types. of support divers depend upon the size of the operation and the type of diving equipment being used. As a general rule, those surface support personnel working directly with the diver should also be qualified divers. The use of nonqualified personnel who do not understand diving techniques and terminology can result in confusion and unnecessary complications. Persons not qualified as divers can be used when the need arises only after they have. demonstrated an understanding of diving procedures to a standard acceptable to the Dive Master.

6.1.3.6 Small-Scale Operations

For self-contained diving operations, a minimum of two divers should be used. In a small-scale operation where the complexity of the assigned task is minimal the Dive Master may dive, and no surface support is required. For an operation of increased scope, or as the tasks to be performed under water increase in complexity, standby divers and even tenders may be required.

6.1.4 Selection of Surface Support Platform

Divers will, during the course of operations, enter the water from many platforms of various sizes and descriptions, ranging from small, inflatable rubber boats to large research vessels. Barges, specially outfitted for diving, may also be used.

Generally, the operational requirements, the type of diving equipment, the magnitude of the diving task, and prevailing and predicted environmental conditions will dictate the surface support platform most desirable to use. For example, nearshore diving using self-contained equipment in relatively calm water may be accomplished without

much difficulty from a good quality boat. More extensive offshore diving operations using selfcontained or umbilical-supplied equipment would be undertaken from a large vessel with adequate deck space (Figure 6-4) or a suitable barge. A complete discussion on surface support platforms is given in Section 14.

6.1.5 Environmental Conditions

Environmental conditions at a dive site play a vital role in planning a diving operation. Generally, environmental conditions can be divided into surface environmental conditions and underwater environmental conditions. Surface conditions include weather, sea state, and ship traffic. Underwater conditions include depth, bottom type, currents, water temperatures, and visibility. Regional and special diving conditions are discussed in Section 9.

6.1.5.1 Surface Environmental Conditions

Weather conditions will be a factor to consider in planning a dive. Whenever possible, diving