TS CWA 16938

TS CWA 16938 provides a common framework for how chemical exposure models should be defined, documented, and communicated to different user groups. Its emphasis is not on prescribing a single exposure calculation method, but on the information that must accompany a model and how that information should be presented consistently.

Core concepts behind exposure-model documentation

In general technical terms, an exposure model is a conceptual or numerical tool used to estimate the likelihood and magnitude of contact between a chemical substance and people, the environment, or workplace settings. In such models, input variables, assumptions, use scenarios, the domain of validity, and the interpretation of outputs are all critical. To understand a model properly, users need more than the final result; they need the conditions under which that result was produced.

How this CWA organises the documentation

This CWA establishes terms and definitions for exposure models and their elements, and specifies the minimum amount of information that should be documented about them. It also proposes a structure for communicating that documentation to different users. As a result, model developers, assessors, regulatory users, and other stakeholders can examine the same model using a shared terminology and a clearer information structure.

• Model name, purpose, and scope
• Terminology and model components
• Input data, assumptions, and limitations
• Guidance on how outputs should be interpreted
• Organisation of information for different user groups

The document is therefore better understood as a documentation and communication standard than as a test method for chemical exposure control or measurement. It is especially useful where model comparison, data appraisal, and information transfer across a model’s life cycle matter. Because TS CWA 16938 is withdrawn, it should be treated as a historical reference document rather than a current active standard, although the technical subject remains relevant.