Blue Water Diving

Blue Water Diving Guidelines

Editor, John Heine

A California Sea Grant

College Program Publication

No. T-CSGCP-014

Purpose

• The purpose of this discussion is to introduce you to the basic procedures and concerns of blue water diving.

Learning Objectives

• Describe conditions in which blue water diving takes place.

• Discuss general procedures and concerns for blue water diving activities.

• Describe a blue water diving rig.

Main Points

• Definition of Blue Water Diving• Extension of the buddy system• Depth control in an environment with no

reference points• Surface platforms• Task distribution• Management of scientific equipment• Emergency procedures

Definition

• Blue water Diving is a specialized diving activity often conducted in clear water with no functional bottom and no reference points for determining depth.

Extension of the buddy system

• Single “Safety Diver”– Responsible for the overall safe execution of

the dive– Communicates with working divers via safety

tethers attached to a “Ring” or “trapeze”– Visibility issues– Pre-arranged signals

Controlling Depth

• Importance– Safety– Working at desired depth in the water column

• Reference Point– Down Line

• Attached to the boat• Depths marked at regular intervals• “Trapeze” or “Ring” attached at appropriate depth

Controlling Depth

• Management Issues– Wind

• Moves the boat and drags the down line

– Waves/Swells• Jerks the line up and down

Surface Platforms

• Size of vessel– Large boats

• Windage issues• Maneuverability issues

– Small boats • Inadequate space to accommodate divers and gear

• Safety Gear• Boat operator qualifications

– Helpful if the operator is a diver

Divisions of Tasks

• Safety Diver– Responsible for the continuation of the dive– Monitor depth and condition each of the divers– Monitor and manage tethers– Scan water for hazards– Monitor environmental conditions

• Working divers– 4-5 maximum (condition dependent)– Perform scientific tasks– Scan water as scientific task permits– Monitor self – Monitor other divers as scientific task permits– Terminate dive if it becomes unsafe

Equipment Management

• Individual flotation devices for each item

• Neutrally buoyant at working depth

• Attached to same down line as divers– Attached as the down line is deployed– Attached above the safety diver and trapeze

– Avoids entanglement issues

• Separate down line for gear

Emergency Management

• Communication protocols set in advance

• Strategies for– Predators

• Safety diver recalls the group to the down line• Group ascends together facing outward

– Weather– Diver Accidents– Equipment issues

Diving Procedures

• Will vary based on environmental conditions and scientific objectives

• Entry into the water– Divers gear up in the boat, attach the safety

tether and drop the safety line overboard behind them

– Divers enter the water & swim to the surface buoy

– Boat operator keeps the surface line slack

Diving Procedures

• Descent– Divers descend as a group to a depth of

approx. 10 feet, and clip into the tether lines on the Trapeze/Ring

– Divers descend as a group to the working depth

– Safety diver attaches the trapeze to the down line and clips in to the trapeze

– Divers go to work

Diving Procedures

• Dive termination– May go up in pairs or as a group– Release the diver safety line and ascend the

down line– Divers regroup at the surface float– Divers exit the water

Summary (Finally)

• Blue water diving is a specialized activity that requires meticulous planning, strong dive skills and teamwork.

• Pre-Dive planning must include (at a minimum)– Extension of the buddy system– Depth control in an environment with no reference

points– Surface platforms– Mission protocols and task distribution– Management of scientific equipment– Emergency procedures– Diving procedures