It describes the requirements to set up a test room comprising a testing area, a preparation area, and an office, specifying those that are essential or those that are merely desirable.

ISO 8589:2007 is not specific for any product or test type.

Although many of the general principles are similar, ISO 8589:2007 does not address test facilities for the specialized examination of products in inspection or in-plant quality-control applications.

The "A" ? "not A" test can be used in sensory analysis in the following ways:

a) as a difference test, particularly for evaluating samples having variations, for example, in appearance (making it difficult to obtain strictly identical repeat samples) or in aftertaste (making direct comparison difficult);

b) as a recognition test, particularly for determining whether an assessor or group of assessors identifies a new stimulus in relation to a known stimulus (for example, recognition of the quality of the sweet taste of a new sweetener);

c) as a perception test, to determine the ability of an assessor to discriminate stimuli.

The "A" ? "not A" test is not appropriate for assessing if two products are sufficiently similar to be used interchangeably (i.e. for similarity testing) because the "A" ? "not A" test inherently involves replicate evaluations of the same products by all assessors. These replicate evaluations violate the basic assumptions for similarity tests to be statistically valid.

Examples of its application are given in Annex B.

NOTE Bi and Ennis[1] point out that the estimate of the discriminal distance, d', between the "A" and "not A" samples is the same regardless of the nature of the replicated evaluations performed in the test but that the estimate of the variance of d' does depend on how the replicate evaluations were performed. As such, no general discussion of a Thurstonian analysis of the "A" ? "not A" method, nor of the power of the test is undertaken in this document. Interested readers are referred to Reference [1] for a detailed discussion of the topic.

This method allows for assessing differences among several samples based on the intensity of a single attribute, of several attributes or of an overall impression. It is used to find if differences exist, but cannot determine the degree of difference that exists between samples.

ISO 8587:2006 is suited for the following cases: a) evaluation of assessors' performance (training assessors, determining perception thresholds of individuals or groups); b) product assessment (pre-sorting of samples, determination of the influence on intensity levels of one or more parameters and determination of the order of preference in a global hedonic test).

ISO 8586-2:2008 sets out requirements for expert sensory assessors to establish sensory profiles of products and materials through the use of descriptors. Specific knowledge of products or materials by expert sensory assessors is not necessary to fulfil these requirements.

ISO 8586-2:2008 supplements the information given in ISO 6658.