Glossary · Testing
A test in which a product is deliberately contaminated with set microorganisms to check that its preservative system reduces them fast enough. ISO 11930 is the standard method.
Regulators and retailers expect this data before a product is placed on the market, and it feeds directly into the safety assessment and the product file.
Guires CSL formulation, testing, clinical and regulatory teams work with Challenge test on client projects every week, from the first brief to the final product file.
ISO 11930 guideRelated terms
Storage of a product at controlled temperatures, humidity and light to check that it keeps its look, smell, texture, pH and active content over its shelf life.
Read definition →Laboratory tests on cells, tissues or chemistry instead of animals, often called new approach methodologies.
Read definition →Regulations and standards are listed first, then peer-reviewed literature. Sources checked October 2026.
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