A calibration laboratory is accredited when it is found to be in compliance with ISO/IEC 17025,  which outlines the general requirements for the competence of testing and calibration laboratories. Accreditation is awarded through an accreditation body that is an ILAC-MRA signatory organization. These accreditation bodies audit the laboratory and its processes to determine the laboratory competent to perform calibrations and to issue their calibration results as accredited.   Accreditation recognizes a lab's competence in calibration and assures customers that calibrations performed under the scope of accreditation conform to international standards.

 The laboratory is audited periodically, to ensure continued compliance with the ISO/IEC 17025 standard.