Laboratory accreditation is that part of the conformity assessment process that recognizes the technical competence of laboratories providing calibration or test data. A2LA accredits all types of laboratories and thus provides one place where a laboratory can achieve accreditation for all of its testing and calibration activities.

A2LA uses ISO/IEC 17025:2005 as the general requirements for accreditation of laboratories. The conditions for accreditation (the laboratory's commitment) and a description of the accreditation process are maintained in A2LA's document General Requirements for Accreditation of Laboratories.

Because of the needs of users (users of accredited laboratories) and specifiers (organizations that require accreditation, including government and private sector), specific technical criteria have been developed to amplify the requirements of the general criteria (ISO/IEC 17025) for several of the programs and fields of testing and calibration.

A separate Scope of Accreditation is given for each field. It lists specific tests, types of tests, or calibrations for which the laboratory has been found competent. For calibration laboratories, scopes of accreditation also include a description of the laboratory's capabilities in terms of measurement parameter, range, best measurement capability expressed as an uncertainty, and technique and/or equipment.

The application for accreditation describes the many technical fields and programs for which a laboratory may apply. These include the programs listed in Table 1.