1.1 The objective of this guide is to provide information to be reviewed and considered by the sensory and consumer scientist who wants to select and use scales to measure responses from consumers or trained assessors. For ease of reading, the term sensory scientist is used throughout the guide when statements apply to the sensory and consumer scientists. 1.2 This guide covers a brief definition of scales as well as some fundamental and practical challenges the sensory and consumer scientists should be aware of when using scales. It also provides a list and a description of the most commonly used scales in the field of sensory evaluation and consumer product research along with a classification framework for these scales. 1.3 The scope of this guide is limited to the sensory and consumer science professional’s selection and use of rating scales when an assessor assigns one symbol/value to one stimulus, to their perception of a stimulus or an internal attitude/opinion. It does not cover: 1.3.1 Details of analysis of data obtained from rating scales, 1.3.2 Guidelines for questionnaire design including attribute selection, 1.3.3 Fundamentals of measurement such as reliability and validity, 1.3.4 Measurement models used to convert scale responses into measures of unobserved sensory or hedonic quantities, 1.3.5 Tasks in which the assessor assigns a symbol/value to a group of stimuli, 1.3.6 Rankings, and 1.3.7 Multi-item scales. 1.4 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.6&