This SAE Recommended Practice describes two dimensional side and rear view 95th and 99th percentile driver and passenger seated head position contours for fixed and horizontally adjustable seats. New information obtained from the SAE Truck Driver Anthropometric and Workspace Study has resulted in development of new head location procedures for trucks and other vehicles with high H-point heights and large steering wheel diameters. Therefore, this practice has been separated into two parts. Part I describes the head location procedure for vehicles with H-point heights (H30) and steering wheel diameters (W9) less than 405 mm and 450 mm, respectively (Class A Vehicles). This class of vehicles includes passenger cars, vans and light trucks. Part II describes a separate head locating procedure for vehicles with H-point heights (H30) between 405 and 530 mm and steering wheel diameters (W9) between 450 and 560 mm (Class B Vehicles). This class of vehicles includes heavy trucks and some buses and multipurpose passenger vehicles (See Fig. 2).