4129 version 2
28-Jun-16
1 of 5
NAVIGATION AND SEAMANSHIP
Control stress, draught and stability of
the ship
level:
5
credit:
32
planned review date:
June 1998
sub-field:
Maritime
purpose:
People credited with this unit standard are able to control the
ballasting operation; maintain stability and stress; and
prepare ballasting system and moveable dead weight items.
entry information:
Open.
accreditation option:
Evaluation of documentation and visit by NZQA and
industry.
moderation option:
A centrally established and directed moderation system has
been established by the Maritime Qualifications New
Zealand (Inc).
special notes:
Rules and regulations include: Standards of Training and
Certification, and Watchkeeping, 1978, Chapter 3,
Resolution 2 and 4; International Maritime Dangerous
Goods Code; International Conference on Training and
Certification of Seafarer, 1978, Chapter 3, Resolution 2 and
4; and International Convention Regarding the Discharge of
Ballast Water.
Ballast systems include: pumps, valves, lines and control
systems.
Stability and stress refers to static and dynamic transverse
stability, longitudinal stability, bending moments, and shear
forces.
 New Zealand Qualifications Authority 2016
4129 version 2
28-Jun-16
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NAVIGATION AND SEAMANSHIP
Control stress, draught and stability of
the ship
Knowledge underpinning this unit standard include: trim and
stability principles and calculations, ship construction, and
exchange of ballast water.
Elements and Performance Criteria
element 1
Prepare ballast systems under the direction of the officer in charge of cargo operations.
performance criteria
1.1
Ballast requirements are pre-determined through consultation with the officer
responsible for planning and co-ordinating the cargo operations.
Range:
details on ballast requirements are obtained from - cargo loading
and discharge plan, ship's drawings, indicators and instruments.
1.2
Ballast systems are prepared in accordance with the requirements specified in
the cargo loading or discharge plan and established safety rules and
regulations.
1.3
Ballast system checks are conducted to ensure their operational effectiveness
and safety.
1.4
Defects in ballast system equipment are assessed and rectified where
necessary or communicated to the officer planning the cargo operations to
ensure any risk to personnel, equipment or the ship is minimised.
 New Zealand Qualifications Authority 2016
4129 version 2
28-Jun-16
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NAVIGATION AND SEAMANSHIP
Control stress, draught and stability of
the ship
element 2
Control ship's ballast operation during cargo operations under the direction of the officer in
charge of cargo operations.
Range:
operations include - loading and discharging; shifting of weights enroute as
consumables are used or replenished.
performance criteria
2.1
The movement of ballast to, from and within the ship is controlled in order to
counteract the stresses placed on the ship's stability and structure during cargo
operations, and to maintain the ship in a stable condition in which cargo
operations may be performed.
2.2
Trim, draughts and list are suitable to progress all ship operations safely and
efficiently.
Range:
operations include voyage.
2.3
The frequency and scope of stability and stress monitoring meet the
requirements of the nature and speed of ship operations, and ensure stress
and stability remain within the ship's operating and statutory limits at all times.
2.4
Action taken where weight distribution has or could lead to the ship exceeding
acceptable limits of stress or stability is prompt and designed to maximise ship
safety.
2.5
Ballast operations are carried out in accordance with instructions received from
the officer responsible for co-ordinating the cargo operations and the
requirements of established safety rules and regulations.
2.6
Malfunctions in the ballast system are assessed and rectified where necessary,
or communicated to the officer planning the cargo operations to ensure any risk
to personnel, equipment or the ship is minimised.
 New Zealand Qualifications Authority 2016
4129 version 2
28-Jun-16
4 of 5
NAVIGATION AND SEAMANSHIP
Control stress, draught and stability of
the ship
element 3
Maintain stability through the movement of dead weight items other than ballast.
Range:
under the direction of the officer in charge of cargo operations.
performance criteria
3.1
The movement of dead weight items other than ballast to, from and within the
ship is controlled in order to counteract the stresses placed on the ship's
stability and structure during cargo operations, and to maintain the ship in a
stable condition in which cargo operations may be performed.
3.2
Trim, draughts and list are suitable to progress all ship operations safely and
efficiently.
Range:
operations include voyage.
3.3
The frequency and scope of stability and stress monitoring meet the
requirements of the nature and speed of ship operations, and ensure stress
and stability remain within the ship's operating and statutory limits at all times.
3.4
Action taken where weight distribution has or could lead to the ship exceeding
acceptable limits of stress or stability is prompt and designed to maximise ship
safety.
3.5
Ballast operations are carried out in accordance with instructions received from
the officer responsible for co-ordinating the cargo operations and the
requirements of established safety rules and regulations.
3.6
Malfunctions in the dead weight items other than ballast system are assessed
and rectified where necessary, or communicated to the officer planning the
cargo operations to ensure any risk to personnel, equipment or the ship is
minimised.
 New Zealand Qualifications Authority 2016
4129 version 2
28-Jun-16
5 of 5
NAVIGATION AND SEAMANSHIP
Control stress, draught and stability of
the ship
Comments to:
Maritime Qualifications New Zealand (Inc)
Unit Standard Revision
PO Box 160
WELLINGTON
by June 1998.
Please Note:
Providers must be accredited by the Qualifications Authority
before they can offer programmes of education and training
assessed against unit standards.
Accredited providers assessing against unit standards must
engage with the moderation system that applies to those unit
standards. [Please refer to relevant Plan ref: 0054]
 New Zealand Qualifications Authority 2016