ISO/IEC 17025:2005 specifies the general requirements for the competence to carry out tests and/or calibrations, including sampling. It covers testing and calibration performed using standard methods, non-standard methods, and laboratory-developed methods.
It is applicable to all organizations performing tests and/or calibrations. These include, for example, first-, second- and third-party laboratories, and laboratories where testing and/or calibration forms part of inspection and product certification.
ISO/IEC 17025:2005 is applicable to all laboratories regardless of the number of personnel or the extent of the scope of testing and/or calibration activities.
ISO/IEC 17025 was first issued in 1999 by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). It is the single most important standard for calibration and testing laboratories around the world. Laboratories that are accredited to this international standard have demonstrated that they are technically competent and able to produce precise and accurate test and/or calibration data.
To fulfill the requirements of the 17025 standard there are 5 basic components that compose the structure to meet the detailed clauses of the standard. They are: scope, procedures, control (including conformance/feedback), uncertainties and proficiencies. Overall, this is again very similar to the structure of ISO9001 in the use of procedures, control and audits. In fact, as far as procedures go, much of the same verbiage in place for an existing quality system can be used in fulfillment of a 17025 compliant system. The common parts to the two quality systems can be in areas like purchasing, document control, quality systems auditing/findings, and correct/preventive action.
The definition of calibration uncertainties is unique to ISO17025 and one core to the specific concept of calibration. The calculation of uncertainties (both systematic measurement bias and random components) is a critical part of both the understanding, operation and report documentation of sensor calibration. In fact, the repeatability of calibration within a prescribed uncertainty is the first level of performance proficiency. The area of uncertainties is typically one of the most intensely discussed during the 17025 compliant system formulation, as well as during the certification audits. It is in this area that practitioners can show that they clearly understand the inner workings / cause and effect of the calibration system measurement choices.