Shipboard diving is quite different from small boat diving or shore-based operations and is, therefore, worthy of comments to aid the inexperienced. At all times it must be understood that the ship's Master has final decisions in any operation concerning his vessel.
NOTE: This article is included to provide historical perspective and to illustrate the long standing, effective, self-regulation of the U.S. research diving community. While some of the details in the sections on Diving Equipment and Diving Procedures are dated, the Cruise Planning, Pre-Dive Procedures and Emergency Procedures sections are quite current. This article was originally published as Shipboard Diving Procedures in Part III of The Scripps Institution of Oceanography Marine Technicians Handbook.
I. Cruise Planning
Any cruise involving diving operations should be planned in advance to allow loading positioning and securing of critical equipment, i.e., compressors, volume bank, diving tanks, etc. The compressor should be positioned with intake toward the bow of the ship (the ship will swing into the wind while at anchor), away from exhausts from main, auxiliary, or any other engines, and free from fume contamination from paint lockers, or gasoline and other solvent handling. Cool running of the compressor requires good ventilation, and should be perhaps used only at night in hot climates. When filling air cylinders, salt water from the ship's sea-water system may be turned on the tanks as a coolant. Oil-lubricated compressors should have some type of oil/water separator built into the system, and it is highly desirable to have a filtration column which eliminates CO, C02, hydrocarbons, oil, water, and any other contaminants in accordance with breathing air specifications. Also desirable is a small calorimetric test kit to determine air quality*. Permanent compressor installations should be under jurisdiction of the ship's engineering staff for maintenance purposes, and a log kept for review of appropriate oil and filter changes.
II. Diving Equipment
Diving equipment should be stored in an area where it can be dried. This designated 'Diving Locker' should be well ventilated and lockable, with the key under the supervision of the ship's Master. Minimum equipment includes two complete sets of the following:
(a) regulators (f) snorkels (b) air cylinders and back packs (g) knives (c) depth gauges (h) weight belts and at least a total (d) masks of 40 pounds of weights (e) fins (with adjustable straps) (i) inflatable life vests
A tank pressure gauge, an assortment of 'goody' bags, and spares of the gear listed above are additional basic requirements. Personal wet suits and watches are provided by each diving individual. Surface signals (flares, whistles) and some sort of anti-shark devices are required in open sea diving. They must be included and used.
III. Pre-Diving Procedures
The ship's Master ultimately has authority over diving operations from his vessel. He should insure that those proposing to dive have proper authorization, either University Certification cards or 'letters of approval.' All diving is to be conducted in accordance with the University Guide for Diving Safety. The Senior Diver, determined during the Cruise Planning phase, will act as liaison with the ship's crew, and act as supervisor of diving operations. His responsibilities include insuring that proper equipment is available in good condition, logging divers in and out of the water, considering emergency and standby equipment and procedures, and maintaining proper records.
Liaison, besides general communication, between diving and other personnel, specifically involves notifying the Master, the ship's engineers, and the cook (garbage overboard is an attractant), of preparations for diving operations, and transmitting a safe go-ahead response to the divers before anyone enters the water.
IV. Diving Procedures
Small boats or rafts are generally necessary for water entry, for use as platforms, or for transportation. A third person, at least, should remain in the boat. Currents often are sufficiently fast to prohibit a diver from swimming up-stream to return to the boat. When a dive is made under the hull or when current direction is known, entry to the water should be made over the bow and the anchor line used for descent; divers obviously should work upstream away from the ship, remembering currents tend to be fastest toward the surface.
Under-way diving necessitates two boat tenders, one to bubble-watch and assist the divers, and one to run the boat. In advance of the exercise the best plan should be determined to permit the divers to stay together while the boat maneuvers to them. Inflatable life vests and anti-shark devices (knives) must be worn/carried in open sea diving work.
Fishing and diving operations must never be carried on simultaneously. If diving under the ship is imperative due to fouling of the propeller, heavy tools ought to be lowered to the diver in a 'goody' bag. One diver, of a pair, should work while a second acts as lookout. (Before any water entry, divers should check to see if sharks are following the ship.)
V. Emergency Procedures
Routines and equipment should be outlined before embarking. The ship's physician should have knowledge of diving accidents and requisite first aid procedures. References such as U.S. Navy Diving Manual should be included in his library. Recompression chambers and the means of getting a diver to one ought to be charted for the entire itinerary.
*These may be obtained from Mine Safety Appliance Corporation, Draeger Corporation and Kitagowa Corporation.