Ocean Diver - Theory Lessons

OT1 - Adapting to the underwater world

Module Objectives

This module provides a basic understanding of air and water pressure and the effects of the underwater environment on the diver. It also covers the purpose and function of diving equipment, and the other specialist kit that divers need, and introduces the concept of buoyancy. Heat loss from the body and how this can be reduced through the proper choice of protective clothing is considered.

Achievement Targets

At the end of this module students should:

• Have a basic understanding of air and water pressure and the physical effects on the diver of the underwater environment
• Understand the purpose and function of basic equipment
• Understand the purpose and function of scuba equipment
• Understand buoyancy
• Understand heat loss, body temperature control and thermal protection options

Equipment Required

• Mask, fins, snorkel, and weight systems
• Scuba equipment – cylinder, regulator with alternative supply, and buoyancy compensator
• Wetsuits and drysuits

OT2 - The body and the effects of diving

Module Objectives

Having introduced how air and water pressure affect divers in relation to basic and scuba equipment in OT1, this module looks in more detail at the human body and the effects of diving on it. Understanding the body provides a background to future modules on diving disorders, prevention and treatment. Diving with nitrox mixes is introduced.

Achievement Targets

At the end of this module students should:

• Have a basic understanding of respiration and circulation
• Understand the need to monitor breathing gas
• Understand the need for general awareness and fitness before diving
• Understand what happens to air spaces in the body when diving
• Have a basic understanding of the effects of nitrogen on the body when diving
• Understand that management of nitrogen is crucial to minimise the risk of decompression illness (DCI)
• Have a basic understanding of breathing gas mixtures and the effect of oxygen on the body when diving

Equipment Required

Dive computers, BSAC dive tables, oxygen analyser, diving cylinder, etc.

OT3 - Going diving

Module Objectives

This module offers practical advice to students on going diving. They may recognise many elements from their practical sessions and here we give guidance on what to expect on dives.

Achievement Targets

At the end of this module students should:

• Know that diving is an adventurous sport and that risks need to be assessed and mitigated to make it as safe as possible
• Understand the importance of diving as a buddy pair
• Understand that diving is controlled by a Dive Manager
• Understand the importance of the dive plan, briefing and buddy check
• Know how to use diving signals
• Know what to expect and what to consider during a dive
• Have a basic understanding of the environment underwater

Equipment Required

Flag, torch, knife, net cutters, compass, etc.

OT4 - Dive planning

Module Objectives

Having walked through what students can expect to happen on an open-water dive in the last session, this module looks in more detail at the basics of dive planning. It reinforces the need for decompression planning and gives practical advice for planning with tables and dive computers. Gas planning and gas toxicity are also covered.

Achievement Targets

At the end of this module students should:

• Know how to manage nitrogen absorption and release to minimise the risk of decompression illness (DCI)
• Understand the terminology used in the BSAC decompression tables and how to use the tables to plan a single dive
• Know how to plan repeat dives with no mandatory decompression stops
• Know the monitoring equipment needed to dive a planned dive
• Understand the basic functions of dive computers and how they can be used for dive planning and diving
• Understand the fundamental differences between dive tables and dive computers and that neither tables nor dive computers are infallible
• Be aware of the effects of altitude on decompression planning
• Be aware of the effects of flying on decompression planning
• Reinforce their basic understanding of oxygen toxicity
• Reinforce the need for gas planning, the use of the rule of thirds to plan gas requirements, and the need to monitor gas on dives

OT5 - What happens if?

Module Objectives

Diver training is “preventive” training; not only when teaching diving skills but also when anticipating how to recognise and resolve problems should they arise. As Ocean Diver students are at an early level of training, some of the areas considered will give them an awareness rather than in-depth knowledge and these will be built on in later diver training grades.

Achievement Targets

At the end of this module students should:

• Understand that anticipating problems is part of dive training and planning
• Understand the importance of the early resolution of underwater problems
• Be aware of the types of problem that divers may encounter
• Know that oxygen administration is a first-aid tool for divers
• Know that recompression treatment should be sought following any abnormalities present after a dive
• Know how to effect a rescue

Equipment Required

• Oxygen administration kit
• SMB/DSMB

OT6 - Enjoying your diving

Module Objectives

When students have completed their Ocean Diver training, they will begin to extend their diving either with a BSAC branch, BSAC centre or on other organised dive trips. They will experience a variety of different dive sites and different diving conditions. This module pulls together what they have already learned and experienced during training and takes it forward because, as qualified divers, they will need to incorporate some of the advice into their planning and diving.

Achievement Targets

At the end of this module students should:

• Know about the different types of dive site and diving conditions that they may experience in the future
• Be aware of the different diving platforms that they may encounter
• Understand the essentials of reef, wreck and night diving
• Understand that reef and wreck divers carry a responsibility to protect the sites for future divers
• Be able to plan for holiday diving, which may take place outside a branch or centre
• Know how to progress their experience once qualified as Ocean Divers

Equipment Required

A diving knife or net cutter, a diving torch, a light stick or strobe light.