1.4 – Overview – Performance Standards

As we discussed in Lesson 1.1 normal operation of a vehicle results in a range of situations where the load may move unless it is restrained and this movement may result in the load leaving the vehicle or causing stability problems for the vehicle.

In lesson 1.2 we discussed how the Mass, Dimension and loading regulations stipulate that

1. A load on a heavy vehicle must not be placed in a way that makes the vehicle unstable or unsafe.
2. A load on a heavy vehicle must be secured so it is unlikely to fall or be dislodged from the vehicle.
3. An appropriate method must be used to restrain the load on a heavy vehicle.

In particular, the regulations specify that a load on a heavy vehicle must be restrained by a load restraint system that:

• Prevents the load from moving in relation to the heavy vehicle (other than movement allowed under the circumstances defined in the regulations.
• At a minimum, is capable of withstanding the forces that are defined in the National Transport Commissions’ Load Restraint Guide (2018).

Examples of load movement that may be permitted under subsection (2)—

A load contained within the sides or enclosure of the heavy vehicle that is restrained from moving horizontally (laterally) may be able to move vertically

A load of very light objects, or a loose bulk load, that is container within the sides or enclosure of the heavy vehicle may be able to move horizontally and vertically

A bulk liquid load contained within the sides or enclosure of the heavy vehicle

Performance Standards (voiceover animation)
The forces that a loaded vehicle must be able to resist are defined in terms of the accelerations on the vehicle. These are

1. 0.8g deceleration in a forward direction;
2. (0.5g deceleration in a rearward direction;
3. 0.5g acceleration in a lateral direction; and
4. if friction or limited vertical displacement is relied on to comply with paragraph (a)—0.2g acceleration in a vertical direction relative to the load.

The loading requirements and loading performance standards define what is required to ensure your load is safe, but they do not specify exactly how you need to restrain your load. The Load Restraint Guide (LRG) which is published by the National Heavy Vehicle Regulatory is the primary source of guidance material on how to practically meet these requirements and is the primary resource material for this course. However, operators may use alternative load restraint methods provided they can show that they meet the requirements and performance standards. This is discussed in more depth in lesson 4.6.

The LRG outlines the two main methods for restraining loads tiedown (Lesson 1.5) and direct restraint (lesson 1.6)