EN ISO/IEC 17 025: Requirements for Sampling

The laboratory shall have a sampling plan and procedure for sampling when it carries out sampling of substances, matrices, materials or products for subsequent testing and calibration. The sampling plan as well as the sampling procedure and shall be available at the location where sampling is undertaken.

Sampling is a defined procedure whereby a part of substance, matrix, material or product is taken to provide for testing or calibration a representative sample of the whole. Sampling can also be required by the appropriate specification for which the substance, matrix, material or product is to be tested or calibrated. In certain cases, the sample may not be representative but determined by availability.

A sampling plan should describe the allocation, withdrawal and preparation of a sample or samples from a substance, matrix, material or product to yield the required information.