Stability testing is a test procedure designed to check the tipping resistance of a vehicle mounted aerial device. All aerial devices are required to undergo this procedure when built, after a major modification is performed, or when a transfer of ownership occurs according to CSA C225-M88. The vehicle must pass both a level and 5 degree angle test with the boom in the most unstable position, fully extended. A load up to twice the rated capacity is applied to the end of the boom and vehicle is checked structurally and for stability. This test must be approved by an engineer.
The US standard, along with CSA C225-M00, calls for a loading of 1 and 1/3 the maximum capacity. For this reason C225-M00 has never been made law in Ontario, and all US imported trucks must be checked for stability prior to being put in service.