TNI Logo The NELAC Institute

Standard Interpretation

Standard: 2016
Section: V1M4, Section


The Standard states that all initial calibrations must be verified by a second source. If a method requires a surrogate or internal standard, do the surrogates and/or internal standards also need to be verified by a second source?


No, V1M4 does not apply to internal standards or surrogates. Section addresses the calibration of analytes. An analyte is defined in V1M2 as "A substance, organism, physical parameter, property, or chemical constituent(s) for which an environmental sample is being analyzed." Internal standards and surrogates do not meet the definition of an analyte.