A non-client sample, as defined by the United States Environmental Protection Agency via its SEDD Specification Version 5.2, is a type of quality control (QC) sample that is different from other QC sample types in that it is simply a regular sample. The EPA adds that "many programs require that certain data be reported from the analysis of non-client samples that were prepared or analyzed with project-specific samples. This is often done to verify run sequences and to ensure that certain QC samples were analyzed at an appropriate frequency. The actual analytical results rarely would be reported."
- SEDD Specification 5.0 http://www.epa.gov/superfund/programs/clp/seddspec5.htm