WOW
I've read all 9 pages and the answers you have gotten are unbelievable.
I am also Canadian with a lot of American friends , so rather than try and convince anyone the importance of an air brake coarse I would like to share a very important truth.
The number one reason for air brake vehicles being grounded at scales is brakes out of adjustment. However all air brake vehicles built since 1995 come equipped with automatic slack adjusters.
They are very reliable but you don't know that if you don't know how to check them and their individual values. I will quit here as I'm not crazy about being insulted for holding an airbrake endorsed license.