The paved area is flat and circular. Although typical pads offer a radius of 300 feet, there are several variations around the world.
A car speeds around the track until the outer tires start to slide, or "skid." The driver is mindful of the edge of the track at all times so as not to exceed the outside radius point.
At the moment the sliding occurs, the speed is clocked. The driver is waved off and decelerates to exit the track.
The car's speed is then plugged into the centripetal force formula to determine the car's lateral handling abilities.
Although primarily used in commercial shoots, police departments often train their officers on skid pads to hone their driving skills. Offered as a course training exercise, officers use the skid pad under various simulated weather conditions to mirror real world conditions.
The pads themselves are made from paved concrete with little padding or buffer zones should a crash occur. Furthermore, motorcycle testing on these pads is a concern because of their high acceleration and slippage factors around turns.