MARM5001A
Calculate, assess and report on vessel trim and stability

This unit involves the skills and knowledge required to assess and report on vessel trim and intact stability as part of the survey function. It is limited to undertaking practical stability tests, simplified stability calculations, reporting inclining experiments and consideration of damage stability implications.

Application

This unit applies to people working in the maritime industry as a domestic commercial vessel marine surveyor and may form part of accreditation requirements for surveyors under Australian legislation.


Prerequisites

Not applicable.


Elements and Performance Criteria

1

Plan and prepare stability testing

1.1

Applicable stability criteria for class of vessel and its operations are identified and confirmed against regulatory requirements

1.2

Differences between Uniform Shipping Laws (USL) and National Standard for Commercial Vessels (NSCV) standards for assessing stability are identified and applied to survey plan as required

1.3

Information and data is used to establish and verify stability characteristics required for safe operation

1.4

Types of stability related hazards that may occur during all types of operations are identified

1.5

Range of intended and/or likely vessel loading conditions are accurately identified and their impact on stability is assessed

2

Calculate vessel trim and stability

2.1

Simplified stability calculations are performed to assess compliance with applicable stability criteria

2.2

Stability assessment methods for equivalent solutions are applied as necessary according to regulatory requirements

2.3

Trim, draughts and freeboard are measured accurately to safely and efficiently allow assessment of compliance with criteria

2.4

Effects of weight distribution that may compromise vessel safety are included in stability assessment

2.5

Computer-based stability programs are used as appropriate to assist with assessing compliance

2.6

Results are verified to confirm compliance

2.7

Vessel is not put at risk during assessment

3

Apply tests, assessments and theories to confirm compliance

3.1

Tests and assessments that could assist to confirm stability compliance are verified and carried out according to safety instructions

3.2

Small angle stability theories are used to establish metacentric height (GM) through transverse movement of weights across vessel deck

3.3

Causes of inaccuracies and limitations of assumptions in tests, assessments and theories are interpreted accurately and considered in stability assessment report

4

Identify other impacts on stability calculations

4.1

Types and effects of damage on vessel stability are identified and considered according to regulatory requirements

4.2

Damage stability considerations are accurately identified and effect of damage is correctly quantified

4.3

Operational impact on stability is identified and considered in compliance assessment

4.4

Vessel safety management plan is reviewed to ensure known or likely impacts on stability are included

5

Document and report findings

5.1

Records are maintained and reports are prepared according to regulatory and organisational guidelines

5.2

Survey report is completed according to regulatory requirements

Required Skills

Required Skills:

Access and interpret a variety of information

Analyse information and data

Anticipate and solve problems that may occur in calculations

Ballast management

Calculate trim and stability using statutory formula and criteria

Carry out a range of different stability tests and assessments

Collate and prepare required documentation

Collect and accurately interpret valid and reliable data and/or regulations

Identify and correct causes of erratic or excessive deviation in mass movements during an inclining experiment

Identify gaps in data and source additional information

Identify hazards, assess risks, and develop and implement risk treatment options

Liaise with relevant people to obtain information

Read and accurately interpret vessel specifications and design drawings

Relate effectively to people from a range of social, cultural and ethnic backgrounds

Resolve conflict and negotiate effectively

Select and use appropriate equipment

Undertake research

Use calculation and stability software

Work independently and unsupervised

Required Knowledge:

Application of vessel construction principles and stability assessments applicable to a wide range of operational contexts

Theories relating to damage stability and precautions to be taken to ensure down-flooding or progressive flooding does not occur

Calculations and formulas related to determining vessel trim and stability

Cargo loading and impact on stability

Configuration and subdivision requirements of a typical vessel including:

collision bulkhead

down flooding

deck edge immersion

freeboard and bulkhead deck

watertight compartments

weather tight compartments

vessel bulkhead

Correct identification and use of equipment and data required for stability tests and calculations

Damage control measures designed to maintain, stabilise or restore hull watertight integrity

Definition of intact stability

Distribution of load on a vessel

Implications and management of free surface effect

Information and data requirements, and statutory documents such as stability book, safety management plans, certificate of operation, vessel history

Naval architectural theory to the level necessary to carry out stability assessments for a range of domestic commercial vessels surveyor is intending to survey

Procedures for:

carrying out an inclining experiment

determining weights to be added or subtracted from calculated displacement to determine lightship displacement

maintaining vessel security and stability

measuring draughts and or freeboard to determine displacement of a vessel i.e. carrying out a lightship measurement

Recordkeeping requirements

Regulatory requirements for:

calculating vessel stability

surveying vessels

vessel compliance to trim and stability

Requirements for conducting a load line survey

Risk management

Safety management procedures and precautions when determining vessel trim and stability

Simplified stability criteria as outlined in NSCV Part C6A and C6C

Survey report requirements

Typical problems and solutions related to vessel trim and stability

Types of simplified stability tests

Work health and safety (WHS)/occupational health and safety (OHS) requirements and safe work practices

Evidence Required

The evidence guide provides advice on assessment and must be read in conjunction with the performance criteria, the required skills and knowledge, the range statement and the Assessment Guidelines for the Training Package.

Critical aspects for assessment and evidence required to demonstrate competency in this unit

The evidence required to demonstrate competence in this unit must be relevant to and satisfy all of the requirements of the Elements, Performance Criteria, Required Skills, Required Knowledge and include:

analysing, planning and assessing trim and stability for at least five different vessels varying size and operational limits

carrying out and reporting on at least three inclining experiments and three lightship measurements

developing effective planning documents

providing high quality reports

performing accurate and reliable calculations

ensuring behaviour reflects relevant current legislative and regulatory requirements.

Context of and specific resources for assessment

Performance is demonstrated consistently over time and in a suitable range of contexts.

Resources for assessment include access to:

industry-approved marine operations site where calculating, assessing and reporting on vessel trim and stability can be conducted

tools, equipment and personal protective equipment currently used in industry

relevant regulatory and equipment documentation that impacts on work activities

range of relevant exercises, case studies and/or other simulated practical and knowledge assessments

appropriate range of relevant operational situations in the workplace.

In both real and simulated environments, access is required to:

relevant and appropriate materials and equipment

applicable documentation including workplace procedures, regulations, codes of practice and operation manuals.

Method of assessment

Practical assessment must occur in an:

appropriately simulated workplace environment and/or

appropriate range of situations in the workplace.

A range of assessment methods should be used to assess practical skills and knowledge. The following examples are appropriate to this unit:

direct observation of the candidate calculating, assessing and reporting on vessel trim and stability

direct observation of the candidate applying relevant WHS/OHS requirements and work practices.

Guidance information for assessment

Holistic assessment with other units relevant to the industry sector, workplace and job role is recommended.

In all cases where practical assessment is used it should be combined with targeted questioning to assess Required Knowledge.

Assessment processes and techniques must be appropriate to the language and literacy requirements of the work being performed and the capacity of the candidate.


Range Statement

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, if used in the performance criteria, is detailed below.

Applicable stability criteria may include:

NSCV guidelines

USL Code

Regulatory requirements may include:

Marine Safety (Domestic Commercial Vessel) National Law

NSCV

Information and data may include:

Cargo information

Load lines

Means to:

sound tanks

read draught marks

Stability book

Tests and assessments may include:

Buoyancy and stability after flooding

Freeboard

Lightship measurement

Practical inclining

Roll period test

Simplified stability tests

Stability proof test

Types and effects of damage may include:

Added mass

Flooding

Large amounts of water on deck

Lost buoyancy

Stability considerations may include:

Ballast management

Closing openings

Damage control measures to maintain, stabilise or restore watertight integrity of hull

Distribution of load on a vessel

Positioning of stowage and lashing of cargo, stores and equipment

Taking action to avoid or minimise cargo shift

Taking precautions when using lifting equipment and other associated equipment

Operational impact may include:

Ballast

Cargo

Crew movement

Cross connections

Lifting gear (including cranes on deck)

Passengers and passenger movements

Towing

Vessel mooring arrangements

Wind /ice and other weather constraints


Sectors

Not applicable.


Employability Skills

This unit contains employability skills.


Licensing Information

Not applicable.