This document provides dimension definitions that facilitate geometric quantification and evaluation of seats. Dimensions described in this document have been designed to be measured in a CAD environment; however, many dimensions require the HPM position and attitude. This can be obtained by physically establishing H-point using benchmark or auditing procedures OR by measuring the HPD within a CAD or modelling system. Refer to the appropriate document for these procedures.These dimensions are package independent in that they do not require use of the HPM-II supplemental thigh/leg/shoe. Three types of seat geometry reference points and measurements have been developed:Simple reference points and measurements not related to H-point.H-point dependent reference points and measurements that utilize the seat characterization capabilities of the HPM to quantify seat measurements.Cross sectional seat trim outlines.For convenience and simplicity, many terms associated with H-point devices use human body parts in their name. However, they should not be construed as measures that indicate interaction with any or all occupants concerning accommodation, human capabilities, or comfort.