What should you keep in mind about emergency braking?

Do not jam on the brakes. Emergency braking does not mean pushing down on the brake pedal as hard as you can. That will only keep the wheels locked up and cause a skid. If the wheels skid, you cannot control the vehicle. Emergency braking means responding to a hazard by slowing the vehicle.
Note: If you drive a vehicle with anti-lock brakes, you should read and follow the directions found in the owner’s manual for stopping quickly.
[California Commercial Driver Handbook]