Unit of competency Outline

Date retreived
24/07/2026 2:29 AM AWST

Whilst all efforts are made to provide accurate and timely information from the relevant source/documentation, please be aware that the information supplied may not be the most current version. The accuracy of the detail has not been confirmed by the Department and therefore should not be relied upon without first confirming the contents.

Dive using self-contained underwater breathing apparatus in open water to 30 metres

Dive using self-contained underwater breathing apparatus in open water to 30 metres

Unit of competency
National Code
DEFDV001B
State Code
AVV02
TGA Status
Replaced
DTWD Status
Replaced
Current Release Number
2.00
Current Release Date
24/01/2013
View on TGA
State Implementation and Classification
Approved Date
Field of Education
092101 - Sport And Recreation Activities
Original Release Date
Nominal Hours
0
Description
This unit covers the competency required to dive using selfcontained underwater breathing apparatus (SCUBA) in an open water environment to a depth of 30 metres.The unit includes planning the dive (including using decompression tables); selecting, inspecting and fitting equipment; entry to the water from a range of platforms; conducting descent to, and servicing time at, the required depth; the ascent (including using decompression techniques); exiting from the water to the original platform; and removing and refurbishing equipment.During the dive, divers must demonstrate situational awareness of their position and orientation, their equipment (including depth, time and air gauges), and other divers. They must be able to communicate (verbally by radio and nonverbally through signalling methods), to navigate underwater, and to manage the range of surface and subsurface hazards inherent to diving.The unit also covers divers’ ability to perceive, both in themselves and others, the signs and symptoms of diving induced medical problems, and to take necessary corrective action/s; and to appropriately react to, and manage, a range of individual and group contingencies/emergencies.Note: This Unit of Competency has been aligned with the existing standards of the Australian Diver Accreditation Scheme (ADAS). This Unit of Competency relates, in part, to the minimum standard for a diver using SCUBA to a depth of 30 metres. ADAS refers to this as ‘restricted’. Further experience is required to gain an ADAS ‘unrestricted’ rating.Tables for both of these ADAS ratings are provided in the Evidence Guide. All information was correct at the time of development of this Unit of Competency; however, any diver seeking ADAS accreditation should consult ADAS and not rely only on the information contained in this unit.
Notes
Elements and Performance Criteria
1. Plan a decompression dive
  • 1.1 Dive plan is constructed using decompression tables.
  • 1.2 Dive plan is discussed and cleared, as necessary, by the supervisor.
2. Select, inspect and fit equipment
  • 2.1 Equipment is selected, inspected for serviceability, fitted and tested if required.
  • 2.2 Any unserviceable equipment is quarantined and defects are reported according to organisational procedures.
  • 2.3 Independent check of fit and function of equipment by a diver's attendant or dive supervisor is ensured.
3. Enter and exit the water
  • 3.1 Markers are positioned in the water to identify the presence of divers.
  • 3.2 Water is entered from sea-borne and land-borne platforms.
  • 3.3 An in-water leak test is conducted at the surface to ensure the integrity and functionality of the equipment.
  • 3.4 In-water checks are conducted.
  • 3.5 Buoyancy is adjusted to commence the dive and as required throughout the dive.
4. Descend to, and ascend from, a 30 m bottom
  • 4.1 Measured and controlled breathing is maintained throughout the dive operation.
  • 4.2 Measured and controlled finning is maintained throughout the dive operation.
  • 4.3 Discomfort is prevented and safety is ensured by descending and ascending at an appropriate rate in accordance with dive plan, using appropriate decompression techniques.
  • 4.4 Diving descent and ascent techniques are implemented.
  • 4.5 Relevant factors are monitored throughout the dive.
  • 4.6 Threats posed are avoided or managed to ensure personal safety.
  • 4.7 Effects of open water environment are considered and managed during the dive to prevent impact against rocks, hulls or interference with other divers.
  • 4.8 Spatial awareness is recovered when balance is lost under conditions of zero visibility.
  • 4.9 When lost and/or separated, recovery is ensured.
  • 4.10Adequate awareness of, and distance from, surface and sub-surface hazards is maintained.
  • 4.11Minimal disturbance to bottom is ensured to enable maximum visibility and a safe work environment.
  • 4.12Safe surfacing is ensured.
5. Identify and manage dive-specific medical problems
  • 5.1 Signs and symptoms of compression related problems are recognised (in self and others) and immediate corrective procedures are taken.
  • 5.2 Signs and symptoms of decompression related problems are recognised (in self and others) and immediate corrective procedures are taken.
  • 5.3 Heat and cold related problems are recognised (in self and others) and immediate corrective procedures are taken.
6. Communicate through underwater radio devices
  • 6.1 Electronic communications device and accessories are inspected for serviceability and fitted.
  • 6.2 Messages are transmitted and received in accordance with radio telephone procedures (RTP).
  • 6.3 Electronic communications device transmission safety requirements are adhered to when working around dangerous items.
  • 6.4 Electronic communications device and accessories are de serviced and stowed.
7. Communicate non-verbally with other divers
  • 7.1 Diver-to-diver hand signals are used appropriately throughout the dive operation.
  • 7.2 Written and diagrammatic communications on underwater writing boards are used appropriately throughout the dive operation.
  • 7.3 Standard single line signals are used appropriately throughout the dive operation.
8. Perform a simple navigation leg underwater
  • 8.1 Compass bearing is maintained underwater using a compass.
  • 8.2 Distance for a constant swim rate underwater is estimated and maintained.
  • 8.3 Distance travelled is estimated using a watch.
9. React to individual and group contingencies/ emergencies
  • 9.1 Flooded face mask is resolved by clearing and refitting.
  • 9.2 Blocked mouthpiece is resolved by clearing and refitting.
  • 9.3 Failed primary breathing system is resolved through switching to the alternate sources.
  • 9.4 Irrecoverable malfunctions are managed through buddy breathing and/or emergency surfacing.
  • 9.5 Lost/severed safety line/s are managed through surfacing.
  • 9.6 Significant systemic failures are managed through the ditching drill and emergency surfacing drill.
  • 9.7 Surfacing is accomplished with the optimum safe speed on hearing the emergency recall signal.
  • 9.8 Other divers are assisted.
10. Maintain equipment
  • 10.1 Equipment is maintained during the dive.
  • 10.2 Post-dive, equipment is de-serviced, and tested (if required) and stowed.
  • 10.3 Unserviceable equipment is quarantined and defects are reported in accordance with organisational procedures.
The Range Statement relates to the Unit of Competency as a whole. It allows for different work environments and situations that may affect performance. Bold italicised wording in the Performance Criteria is detailed below.
Decompression tables may include:
Defence Civil Institute of Environmental Medicine
Equipment may include:
breathing system and devices:
cylinder
configuration
demand
independent primary
pressure
positive
single
supply
buoyancy devices:
buoyancy compensator
weight belt
dive clothing:
fins
gloves
wetsuit (includes booties and hood)
diving accessory equipment:
communications slate
compass
face mask/mouthpiece ensemble
knife
watch
safety equipment:
diver’s safety lines
Entry to the water may include:
dive
forward/backward jump
rollback
walkin (backwards)
Platforms may include:
boats
semipermanent platforms
ships
Buoyancy includes:
positive
negative
neutral
Decompression techniques may include:
lazyshot and drifting stops
lazyshot and fixed shot rope
lazyshot and float line
lazy shot and life line
surface
Diving descent and ascent techniques may include:
breathing
buoyancy maintenance
equalisation
maintaining situational and positional awareness throughout the dive
monitoring equipment and gauges
propulsion
surfacing
Relevant factors may include:
air
depth
equipment
location
other divers
time
Threats may include:
pollution
weed
other debris
Effects of open water environment may include:
currents
swells
wave action
Ensuring recovery may include:
employing rendezvous procedures
surfacing
Surface and subsurface hazards may include:
anchor drop zones
cathodic protection devices
electrical cabling
inlets and sonar/radio frequency hazards
marine animals
piers and jetties
pipelines
pollutants
propellers/thrusters
trapping hazards:
beams
culverts
gates
grottoes and caves
intakes and outfalls
nets
safety, anchor and communications lines
sluices
sewers
submerged ships, vehicles and structures
vessel rocking and associated movement
Ensuring safe surfacing must include:
checking for the sounds of propellers before committing to breaching the surface
advancing the arm above the head for protection and signalling, and once surfaced, gaining 360 degree awareness
Electronic communications device may include:
topside/surface
subsurface divers systems:
hard wire
through water voice
Accessories may include:
antenna
ear set
microphone
Radio telephone procedures may include:
callsigns
phonetic alphabet
prowords
relaying messages
words twice procedures
Dangerous items may include:
explosives
Assisting other divers may include:
physically recovering a diver to the surface using the ‘companion diver’ drill (including unconscious companion)
searching for a lost buddy
sharing air supply through buddy breathing
Critical aspects for assessment and evidence required to demonstrate competency in this unit
Assessment must confirm the ability to:
safely enter and exit the water appropriate to the launch platform, equipment and conditions
avoid and manage medical complications during dives
avoid and manage hazards during dives
comply with assigned callsigns
act as a relay between two callsigns
receive a number of hand signal messages, demanding acknowledgement, interpretation and appropriate responses from the diver
relay hand signal message to other divers
receive a number of written messages including diagrams, demanding acknowledgement, interpretation and appropriate responses from the diver
draft a number of written messages including diagrams
receive a number single line signal messages, demanding acknowledgement, interpretation and appropriate responses from the diver
navigate underwater, using a compass only, a complete triangle, of side length not less than 30 m (waypoints only to be distinguishable within 8 m).

Consistency in performance
Competency will be demonstrated over a minimum of 12 (ADAS Pt 1 Restricted) dives with the diver diving to 30 m using SCUBA (air) in open water that includes the following requirements:
day and night
subsurface conditions:
current (0-2 knots)
visibility (0 metre +)
temperature (0 degrees +)
range of surface and subsurface hazards.
Table 1 (below) outlines the minimum dives required by this Unit of Competency. At the time of printing, this contributed to the achievement of an ADAS Pt 1 (restricted) license, however divers seeking ADAS licensing need to confirm details with ADAS.
Table 1
Condition
No of Dives
Bottom time (mins)
Remarks
Between 030m
12
325
Represents total accrued - refer ADAS Pt 1 Restricted (Science Diver)
Special Qualifiers
2530m dive
1
15

Zero visibility
1
20
Depth: 29 m
Night
(+30 mins sunset/
sunrise)
1
20
Depth: 10 m

Table 2 (below) outlines the minimum dives required for an ‘unrestricted’ ADAS Pt 1 license, however divers seeking ADAS licensing need to confirm details with ADAS.
Table 2
Condition
No of Dives
Bottom time
(mins)
Remarks
Between 030m
21
660
Represents total accrued - refer ADAS Pt 1 Diver
Special Qualifiers
2830 m dive
1
15

Zero visibility
2
20 (per dive)
Depth: 29 m
Night (+30 mins sunset/
sunrise)
1
20
Depth: 29 m

Context of and specific resources for assessment
Context of assessment
Competency will be assessed in the ocean over a range of oceanic, diurnal and nocturnal environments, supported by questioning on shore or aboard vessels.
When practicable, assessment should relate to the diver’s vocational focus.
Specific resources for assessment
Access to a complete range of diving, safety and accessory equipment; open water dive site; and dive platform.
Replaced By
State Code National Code Title Type
BBC60 DEFWDV001 Dive using self-contained underwater breathing apparatus in open water to 30 metres Unit of competency
No information