An exclusion audit is a tool to evaluate different products or concepts by comparing the proportion of the population that will be unable to use them. This allows design decisions to be based on meaningful numbers, but requires greater levels of knowledge, resources and time than a capability assessment. A task analysis is used to record the activities that are necessary to use the product, then the capability demands of these activities are assessed in terms of the levels of exclusion that result.

Objective scales may be used to measure the level of capability that a product or service demands in order to use it. Once the appropriate demand level has been identified, the data from the 1996/97 Disability Follow-up Survey can provide the number of people that will be excluded. The statements used to describe the anchor points, and the graphs for each different capability type can be found within the User capabilities section.

Since any product interaction usually requires a particular sequence of tasks, and each task may require the use of multiple capabilities, a more complex calculation is often required. In this case, the Exclusion calculator within Links & resources) can be used.