Transport regulations set out the rules for carrying loads on vehicles.
These include the maximum dimensions of loads a vehicle is permitted to carry:
- the maximum length, height, width and;
- front, rear and side projections (or overhang) allowed for the vehicle
- the maximum weight a vehicle or trailer is permitted to carry and that loads are to be adequately secured.
Breach any of these rules and you could be issued with an on-the-spot fine or in the event of damage to property or injury to persons, considerably more substantial penalties.
This fact sheet provides links to the various documents you will need to determine if a particular load can legally be carried on your vehicle. It also contains links to information about appropriate methods of securing loads as well as explanations of certain terminology relating to this issue.
Can be found in the Department of Transport and Main Roads brochure Projecting Loads
(pdf, 210kb) which outlines the maximum dimensions of loads permitted in Queensland. Note that this brochure covers both light and heavy vehicles, but only those requirements relating to light vehicles and their trailers will be relevant to this discussion.
The term ‘pig trailer’ is used in this brochure to describe the arrangement typical of the majority of light trailers. A ‘pig’ trailer utilises fixed, non-steering axle/s while a ‘dog’ trailer has a steerable front axle.
For commercial vehicles such as trucks and utilities, the maximum weight you are permitted to carry is known as the vehicle’s payload. It is the difference between its Tare (un-laden) Weight and its Gross Vehicle Mass (GVM), and also includes passengers. Passenger vehicles do not usually have a payload specification as they are not intended to carry any significant loads.
The maximum weight a trailer can carry is specified as either its Aggregate Trailer Mass (ATM) or Gross Trailer Mass (GTM).
Aggregate Trailer Mass
- ATM is the combined weight of the trailer and its full load when it is not coupled to a tow vehicle.
Gross Trailer Mass
- GTM is the weight of the fully loaded trailer that is imposed on the trailer’s axle when it is coupled to the tow vehicle. GTM will always be less than ATM as some of the trailer weight is transferred to the tow vehicle when the trailer is coupled to it.
GTM is most commonly used and most un-braked single axle (domestic type) trailers will have a GTM of 750kg.
All trailers built since August 1989 are required to have a plate listing the trailer’s ATM. Some will also show the GTM.
Gross Combination Vehicle Mass GCVM
- GCVM (where given) is the maximum allowable weight of the trailer, tow vehicle and the load in the tow vehicle and trailer (including passengers). GCVM is usually only specified for vehicles that can carry a load (such as vans and utilities) and tow a trailer.
For further information on trailers and towing refer to our Towing fact sheet
Restraining the load
Queensland legislation requires loads to be properly secured. Fines can be issued for loads that fall off vehicles and trailers, or for loads that are considered to be in danger of falling off. Be aware though that in the event of damage to property or injury to persons, caused by loss of a load, considerably more substantial penalties may result.
How you meet the legal requirements to effectively secure a load is largely up to you, though suggested methods are outlined in the Load Restraint Guide
(pdf, 5.5MB) published by the National Transport Commission.
The above document is very detailed and is intended for use in the heavy transport industry, though the principles it contains apply equally to light vehicles such as utilities and trailers. However the Loads and Towing Standards document from the Department of Transport and Main Roads is a simplified version intended for light vehicle operators and provides information about restraining many of the types of items typically carried on utilities and small trailers.
Ropes, straps and nets for securing loads
Rope intended for transport use (Transport Fibre Rope complying with AS/NZS 4345) is acceptable for securing loads. However some rope commonly used in light vehicle applications may not be suitable for this purpose as its load capacity will be unknown and it may not be possible to determine with any certainty if it is capable of restraining the load in question. Also some rope types are not well suited to holding load securing knots as they are prone to slippage. Be aware though that rope is only suitable for certain types of light loads due to the limited tension that can be applied by it.
The user’s ability to tie appropriate knots can also be a limiting factor. See section 5 and 6.3 of the Load Restraint Guide
for more information about the types of knots considered appropriate for securing loads with ropes.
From a practical point of view, ratchet cargo straps offer a number of advantages over rope. They are readily available, low cost, and require little skill to use. Many users, including heavy vehicle operators, find them to be an effective and convenient method of securing loads, but we recommend that you only buy and use straps that are marked with a load rating appropriate for your particular application.
Cargo nets are an easy and versatile way to secure light, loose articles and they are commonly seen on tradesmen’s utilities and domestic trailers. Their use is not mandatory but they are one of a range of load restraint options that are acceptable when used in the right application.
See section 4.12 and 4.13 of the Load Restraint Guide
(pdf, 5.5MB) for further information on ropes and cargo straps.
Regardless of the restraint type you choose, it’s important to understand that some loads, particularly vegetation and other compressible materials, settle and move in transit, which means that the restraints can lose tension. It’s therefore good practice to check, and if necessary, tighten the restraints during the trip. Ropes, due to their inability to apply high tensions, are more likely to loosen than other types of restraint.
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