| 2. Glossary The following section contains the definitions of a number of terms in the sense in which they are used throughout this Handbook. Where applicable, definitions are taken from: 1) NIST Handbook 150, NVLAP Procedures and General Requirements, 1994, wherever possible; 2) The International Vocabulary of Basic and General Terms in Metrology (VIM: 1994); or 3) NIST Handbook 143, Program Handbook, 1985 edition. Many of the NIST Handbook 150 definitions are taken from the VIM:1994. Accreditation - a formal recognition that a laboratory is competent to carry out specific tests or calibrations or types of tests or calibrations. (HB 150) Accreditation Criteria - a set of requirements used by an accrediting body which a laboratory must meet in order to be accredited. (HB 150) Accreditation Process - the process of demonstrating whether a calibration laboratory is capable of fulfilling specified accreditation requirements. Approved Signatory (of an accredited laboratory) - an individual who is recognized by OWM as competent to sign official laboratory calibration or test reports. (HB 150, modified) NOTE: The Approved Signatory is responsible for the technical content of the report and is the person to be contacted by OWM, laboratory clients, or others in case of questions or problems with the report. Approved Signatories shall be persons with responsibility, authority, and technical capability within the organization for the results produced. The laboratory must maintain a list of Approved Signatories and make that list available for review during on-site assessments and to OWM upon request. Authorized Representative (of a recognized laboratory) - an individual who is authorized by the laboratory or the parent organization to sign the OWM Request for Recognition form and commit the laboratory to fulfill the OWM requirements. (The Authorized Representative may also be recommended by the laboratory as an Approved Signatory. Only the Authorized Representative can authorize a change in the scope or nature of the laboratory's Request for Recognition.) (HB 150, modified) Calibration - a set of operations which establish, under specified conditions, the relationship between values indicated by a measuring instrument or measuring system, or values represented by a material measure, and the corresponding known values of a measurand. (HB 150) Also: comparison of a measurement standard or instrument with another standard or instrument to detect, correlate, report, or eliminate by adjustment any inaccuracy of the compared. Certificate of Traceability - a certificate issued to a weights and measures laboratory indicating that the laboratory has traceable standards, can make and provide traceable measurements, and complies with the requirements of NIST Handbook 143, Program Handbook. Corrective Action - an action taken to eliminate the causes of an existing deficiency or other undesirable situation in order to prevent recurrence. Deficiency - the nonfulfillment of NIST/OWM conditions and/or criteria for accreditation. (HB 150, modified) Good Laboratory Practices (GLP) - an acceptable way to perform some basic operation or activity in a laboratory, that is known, or believed to influence, the quality of its outputs. GLPs ordinarily are essentially independent of the measurement techniques used. (HB 143, 1985) Good Measurement Practices (GMP) - an acceptable way to perform some operation associated with a specific measurement technique, and which is known or believed to influence the quality of the measurement. (HB 143, 1985) Interlaboratory Comparisons - organization, performance and evaluation of calibrations or tests on the same or similar items or materials by two or more laboratories in accordance with predetermined conditions. (HB 150) Internal Assessment - the process of self-appraisal of a calibration or testing laboratory using specified general and technical criteria and checklists to evaluate compliance to accreditation requirements; may be used as a quality management review as well. Laboratory - an organization that performs calibrations and/or tests. When a laboratory is part of an organization that carries out activities additional to calibration and testing, the term "laboratory" refers only to those parts of that organization that are involved in the calibration and testing process. The laboratory activities may be carried out at or from a permanent location, at or from a temporary facility, or in or from a mobile facility. (HB 150) Length Laboratory - a specific area, within a metrology laboratory, that is used solely for calibration or tolerance testing of length standards. (HB 143, 1985) Mass Laboratory - a specific area, within a metrology laboratory, that is used solely for calibration or tolerance testing of mass standards or test weights; generally divided into small mass ( £ 10 kg) and large mass (> 10 kg) areas. (HB 143, 1985) Measurement Assurance - a process to ensure adequate measurement results that may include, but is not limited to: 1) use of good experimental design principles so that the entire measurement process, its components, and relevant influence factors can be well characterized, monitored, and controlled; 2) complete experimental characterization of the measurement process uncertainty including statistical variations, contributions from all known or suspected influence factors, imported uncertainties, and the propagation of uncertainties throughout the measurement process; and 3) continuously monitoring the performance and state of statistical control of the measurement process with proven statistical process control techniques including the measurement of well-characterized check standards along with the normal workload and the use of appropriate control charts. (HB 150) NVLAP - the NIST National Voluntary Laboratory Accreditation Program. On-Site Assessment - a formal examination or official inspection of a calibration or testing laboratory to evaluate its compliance with specific laboratory accreditation criteria. OWM - The NIST Office of Weights and Measures (Weights and Measures Program). Proficiency Testing - the determination of laboratory performance by means of comparing and evaluating calibrations or tests on the same or similar items or materials by two or more laboratories in accordance with predetermined conditions. (HB 150) Preventive Action - an action taken to eliminate the cause of a potential deficiency or other undesirable situation in order to prevent occurrence. Quality Audit - a systematic and independent examination to determine whether quality activities and related results comply with planned arrangements and whether these arrangements are implemented effectively, and are suitable to achieve objectives. (HB 150) Quality Control - the operational techniques and activities that are used to fulfil requirements for quality. Quality Manual - A document stating the quality policy, quality system, and quality practices of an organization. The quality manual may reference other laboratory documentation. (HB 150) Recognition - the evaluation and issuance of a certificate of traceability and letter regarding the laboratory quality system for weights and measures laboratories (not a formal accreditation). RMAP - Regional Measurement Assurance Program. A regional approach to ensuring measurement assurance through periodic gathering to conduct training, interlaboratory comparisons, and continuous improvement activities. OWM jointly operates six regional MAPs in cooperation with the State laboratories. Scope of Accreditation - A document issued by an accreditation body which lists the test methods or services, or calibration services for which the laboratory is accredited. The scope for each measurement area includes the range and the best uncertainty reported at each level. (HB 150) Standard, Check (or control) - a standard that is used as part of a process measurement assurance program to provide a "check" on the process and standards to ensure that the standards, measurement results, and measurement processes are within acceptable statistical limits. Standard, Intrinsic - Intrinsic standards are based on well-characterized laws of physics, fundamental constants, or invariant properties of materials, and they make ideal stable, precise, and accurate measurement standards if properly designed, characterized, operated, monitored and maintained. (NCSL, Traceability Resolution Meeting. 1/25/96) Standard, Primary - A standard that is designated or widely acknowledged as having the highest metrological qualities and whose value is accepted without reference to other standards of the same quantity. (HB 150) Standard, Reference - A standard, generally of the highest metrological quality available at a given location, from which measurements made at that location are derived. (HB 150) Standard, Secondary - a standard whose value is assigned by comparison with a primary standard of the same quantity. (HB 150) Standard, Working - a standard that is usually calibrated against a reference standard, and is used routinely to calibrate or check material measures, measuring instruments, or reference materials. (HB 150) Standard Operating Procedure (SOP) - a procedure adopted for repetitive use when performing a specific measurement or sampling operation. It may be a standard method or one developed by the user. (HB 143, 1985) State Laboratory Program - A program of the NIST Office of Weights and Measures designated to provide guidance, technical support, and assistance to State legal metrology laboratories to ensure accurate and traceable measurements from NIST to the local jurisdictions. Temperature Laboratory - a specific area, within a metrology laboratory, that is used solely for calibration or tolerance testing of temperature standards. Tolerance Testing - a measurement operation performed to determine whether the actual value of a standard, artifact, or instrument is within a permitted tolerance of its nominal value. An error and uncertainty value must first be determined before one can assess the tolerance status. (HB 143, 1985) Traceability - the property of the result of a measurement or the value of a standard whereby it can be related to stated references, usually national or international standards, through an unbroken chain of comparisons all having stated uncertainties. (VIM:1994) A measurement quality assurance system and periodic verification are required to ensure that the accuracy of the measurement is within the stated limits of uncertainty. Uncertainty - parameter, associated with the result of a measurement, that characterizes the dispersion of the values that could reasonably be attributed to the measurand. (HB 150) Volume Laboratory - a specific area, within a metrology laboratory, that is used solely for calibration or tolerance testing of volume standards; generally divided into small volume ( £ 20 L) and large volume (> 20 L) areas. (HB 143, 1985) | 