"Passenger car equivalents" is a measure of the operational or structural impact on the road system of a specified type and size of heavy vehicle expressed in terms of the number of standard passenger cars that would create the same impact as the specified heavy vehicle. For example, a large truck determined to be four passenger car equivalents, would be expected to cause the same impacts on the level of service of the road system as four standard passenger cars. (Added by Amended Ord. 05-083, Dec. 21, 2005, Eff date Feb. 1, 2006).