Elements and Performance Criteria

The range of variables places the competency in context and allows for differences between enterprises and workplaces, including practices, knowledge and requirements. The range of variables also provides a focus for assessment and relates to the unit as a whole. The following variables may be present.

Compression chamber:
· twin-lock
· single-lock
· transportable.

Limitations:
· size
· layout
· transportability
· gas supplies:
· oxygen
· air
· mixed gases
· equipment backup.

Therapeutic tables:
· US Navy
· Royal Navy.

Standards:
· Australian standards
· guidelines
· codes of practice
· Occupational Health and Safety regulations
· other regulations.

Hazards:
· overconfidence
· loss of dexterity
· task fixation
· anxiety
· panic
· claustrophobia
· hallucinations
· narcosis.

Risk control:
· briefing
· supervisor
· qualified diver
· emergency procedures.

Each unit of competency has an evidence guide that relates directly to the performance criteria and the range of variables. Its purpose is to guide assessment of the unit in the workplace and/or training program. The following components provide information to assist this purpose.

Underpinning knowledge
The underpinning knowledge identified for this unit is comprehensive due to its likely inclusion in a group of units that may be used as the basis for the issue of licences by regulatory bodies.

The essential knowledge and understanding a person needs to perform work to the required standard include:
· layout, functions, uses and limitations of compression chambers
· symptoms and effects of nitrogen narcosis
· the effects of physiological and environmental changes on a person in a compression chamber
· safety procedures in relation to compression chambers.

Practical skills
The essential skills a person needs to perform work to the required standard include:
· preparing a chamber prior to a dive
· undertaking a chamber dive to 50 metres using a built-in breathing system to breathe oxygen at a maximum depth of 10 metres
· experiencing symptoms and effects of nitrogen narcosis
· performing simple comprehension or dexterity tests
· undertaking a psychological test at the surface and at 50 metres in a compression chamber
· performing post-dive cleaning and maintenance.

Literacy skills used for:
· performing comprehension or dexterity tests.

Numeracy skills used for:
· performing comprehension or dexterity tests.

Critical aspects of competence
Assessment must confirm the ability to:
· undertake a chamber dive to 50 metres using a built-in breathing system
· perform appropriate tests relevant to chamber dives.

Assessment must confirm knowledge of:
· compression chambers
· nitrogen narcosis
· safety procedures.

Interdependent assessment of units
This unit may be assessed after/with:
· No recommendations.

Context of assessment
Assessment is to be conducted at the workplace or in a simulated work environment.

Method of assessment
The following assessment methods are suggested:
· observation of practical demonstration
· written or oral short answer testing
· practical exercises
· project work.

Resources required for assessment
Resources may include:
· compression chamber with built-in breathing system and other associated equipment
· communication system.