This document provides a comparative scale (no judgement) of motion-related comfort onboard yachts to be used for technical and commercial benefit. The scale consists of a maximum number of 5 stars, the higher the amount of stars, the higher the comfort onboard. It allows the selection of the most suitable yacht for a specific purpose, evaluates the impact of stabilization systems, compares designs and identifies the most comfortable position onboard.

The methodology, work flow and criteria proposed in this document are subject to possible improvements and do not take into account certain important aspects that influence the comfort onboard.

The following aspects are not covered in this document: jerk, the method to derive roll damping, stern quartering seas, risk of parametric roll, the influence of the steering devices, green water and waves impacts, compensation for yacht size, gender and age dependency, habituation.

By explicitly listing the aspects that are not covered in this document, the reader becomes aware of them and can improve the assessment with dedicated considerations.