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Demonstrate knowledge of overweight and overdimension vehicle dynamics for safe driving

Level / 4
Credits / 6

PurposeThis unit standard is for drivers of vehicles with overweight and overdimension loads.

People credited with this unit standard are able to: describe the swept path of a specified loaded vehicle; describe how a load’s position on the vehicle trailer(s) affects stability; describe the preparation and techniques for maintaining load stability; describe the effects of weather conditions in terms of transporting a heavy haulage load; and describe the driving techniques for travelling downhill when transporting a heavy haulage load.

Subfield / Commercial Road Transport
Domain / Heavy Haulage
Status / Registered
Status date / 21 September 2007
Date version published / 21 September 2007
Planned review date / 31 December 2012
Entry information / Recommended: Unit 18079, Demonstrate knowledge of heavy combination vehicle dynamics and handling for safe driving, or demonstrate equivalent knowledge and skills.
Accreditation / Evaluation of documentation and visit by NZQA and industry.
Standard setting body (SSB) / NZ Motor Industry Training Organisation (Incorporated)
Accreditation and Moderation Action Plan (AMAP) reference / 0092

This AMAP can be accessed at

Special notes

1Legal requirements to be complied with include:

Land Transport Act 1998;

Land Transport Rule: Heavy Vehicles 2004;

Land Transport Rule: Heavy-vehicle Brakes 2006;

Land Transport Rule: Vehicle Dimensions and Mass 2002;

Traffic Regulations 1976.

2Any new, amended, or replacement Acts, regulations, Rules, standards, codes of practice, Land Transport New Zealand or Transit New Zealand requirements or conditions affecting the outcome of this unit standard will take precedence for assessment purposes, pending review of this unit standard.

3References

The Official New Zealand Truck Loading Code – Code of Practice for the Safety of Loads on Heavy Vehicles (current edition), available from booksellers;

The Transit New Zealand Overweight Permit Manual SM070 1995,available at the Transit New Zealand website

4Definitions

Organisational requirements include any legal requirements, standards, codes of practice, organisational and/or site requirements, industry best practice, and manufacturers’ instructions. These must be available to candidates, providers, and assessors;

The Rule is Land Transport Rule: Vehicle Dimensions and Mass 2002;

Road furniture is pedestrian refuges, power poles, stop and give-way signs, street signs, telephone poles, threshold signs, traffic control signs such as traffic lights, and any other items that are positioned on or near a road and that need to be considered by an operator in relation to an overdimension load vehicle fitting the route;

Road geometrics include but are not limited to – width, camber, crossfall, gradient, surface, horizontal and vertical curvature;

Swept path means the maximum road width required by a vehicle when it negotiates a turn;

A vehicle is a combination vehicle.

Elements and performance criteria

Element 1

Describe the swept path of a specified loaded vehicle.

Performance criteria

1.1The description includes the amount of road space required to pass through, the trailer swing arc, and load tail swing outwards.

1.2The description identifies the boundaries of available roadway for both vehicle and load.

1.3The description includes the amount of roadway required between road furniture and structures to allow the load to safely pass.

Element 2

Describe how a load’s position on the vehicle trailer(s) affects stability.

Performance criteria

2.1The description includes an explanation of the stability triangle in relation to load positioning.

2.2The description includes the effect of load position on vehicle traction.

2.3The description includes the effect of load position on jack-knifing.

2.4The description includes the effect of the alignment of the load divider and the trailer on stability.

Element 3

Describe preparation and techniques for maintaining load stability.

Performance criteria

3.1The description includes completing a route survey and temporary removal of road furniture in accordance with the Rule and organisational requirements.

3.2The description includes driving techniques to maintain load stability in relation to road geometrics and permanent road fixtures such as kerbs and traffic islands.

3.3The description includes trailer adaptation and steerable axle positioning to maintain load stability.

3.4The description includes the use of braking systems to maintain load stability.

Element 4

Describe the effects of weather conditions in terms of transporting a heavy haulage load.

Performance criteria

4.1The description includes the need to monitor weather forecasts and weather conditions en route.

4.2The description includes techniques to counter the effect of tail winds on vehicle engine cooling.

4.3The description includes techniques to counter the effect of rain, snow, and fog on visibility and/or load stability.

4.4The description covers situations where the vehicle must be stopped en route because of weather conditions.

4.5The description covers situations where the load must be protected because of weather conditions.

4.6The description includes techniques to prevent damage to a sealed road surface in bleeding tar conditions.

4.7The description includes techniques to counter the effect of ice on the road surface.

Element 5

Describe driving techniques for travelling downhill when transporting a heavy haulage load.

Performance criteria

5.1The description includes speed selection in relation to the gradient and gradient length, load mass and size, load position, and load stability triangle.

5.2The description includes gear selection, engine braking, use of a fitted retarder, use of service brakes, and ancillary braking systems.

Please note

Providers must be accredited by NZQA, or an inter-institutional body with delegated authority for quality assurance, before they can report credits from assessment against unit standards or deliver courses of study leading to that assessment.

Industry Training Organisations must be accredited by NZQA before they can register credits from assessment against unit standards.

Accredited providers and Industry Training Organisations assessing against unit standards must engage with the moderation system that applies to those standards.

Accreditation requirements and an outline of the moderation system that applies to this standard are outlined in the Accreditation and Moderation Action Plan (AMAP). The AMAP also includes useful information about special requirements for organisations wishing to develop education and training programmes, such as minimum qualifications for tutors and assessors, and special resource requirements.

Comments on this unit standard

Please contact NZ Motor Industry Training Organisation (Incorporated) if you wish to suggest changes to the content of this unit standard.

 New Zealand Qualifications Authority 2018