
To view PDF files, you must have a copy of the Adobe Acrobat Reader which is available as a free download.
![]()
The Spring Road Restriction levels are based on percentage loading formulae that are simpler and easier to use. Two restriction levels provide higher truck loading where possible and protect pavements where necessary. Exceptions to these restrictions will be made only for steering axle weights and Essential Commodities as described below. A Maximum Allowable Weight Table is included in this page to show examples of allowable loading for each restriction level.
Load restriction levels for all axle units, except steering axles in certain situations, are expressed as a percentage of normal loading for each highway class:
Level 1 Restrictions:
- RTAC Routes, class A1 & B1 Highways: 90 % of normal axle loads
Level 2 Restrictions:
- class A1 & B1 Highways: 65 % of normal axle loads
Tire size allowable weight information is available here:
To address technological changes, such as set back steering axles, the allowable weights for steering axles are as follows:
Level 1 Restrictions:
- Normal loading of 10 kg/mm of tire width to a maximum of 5,500 kg will be allowed.
Level 2 Restrictions:
MAXIMUM ALLOWABLE WEIGHTS (in kilograms)1 |
||||
Example for Truck-Tractor and Semi-Trailer with 280 mm/11 inch Tires |
||||
| Axle Loading | Steering Axle | Single Axle | Tandem Axle | Tridem |
| RTAC 90% (normal) | 5,500 (5,500) | 8,190 (9,100) | 15,300 (17,000) | 20,700 (23,000) |
| A1 90% (normal) | 5,500 (5,500) | 8,190 (9,100) | 14,400 (16,000) | 20,700 (23,000) |
| A1 65% | 3,575 | 5,915 | 10,400 | 14,950 |
| B1 90% (normal) | 5,500 (5,500) | 7,380 (8,200) | 13,050 (14,500) | 18,000 (20,000) |
| B1 65% | 3,575 | 5,330 | 9,425 | 13,000 |
| 1 Detailed maximum allowable weight tables are available above. | ||||