(1) The measurement of dose or contamination for reasons related to the assessment or control of exposure to radiation or radioactive substances, and the interpretation of the results. 1] Measurement is used somewhat loosely here. The measurement of dose often means the measurement of a dose equivalent quantity as a proxy (i.e. substitute) for a dose quantity that cannot be measured directly. Also, sampling may be involved as a preliminary step to measurement. Monitoring may be subdivided in two different ways: according to where the measurements are made, into individual monitoring, workplace monitoring, source monitoring and environmental monitoring; and, according to the purpose of the monitoring, into routine monitoring, task related monitoring and special monitoring. Area Monitoring: A form of workplace monitoring in which an area is monitored by taking measurements at different points in the area. As opposed to measurements by a static monitor. Environmental Monitoring: The measurement of external dose rates due to sources in the environment or of radionuclide concentrations in environmental media. Contrasted with source monitoring. Individual Monitoring: Monitoring using measurements by equipment worn by individual workers, or measurements of quantities of radioactive materials in or on their bodies. Also called personal monitoring. Usually contrasted with workplace monitoring. Personal Monitoring: Synonymous with individual monitoring. This usage may be confusing and is discouraged in favour of individual monitoring. Personnel Monitoring: A combination of individual monitoring and workplace monitoring. This usage may be confusing and is discouraged in favour of individual monitoring and/or workplace monitoring, as appropriate. Routine Monitoring: Monitoring associated with continuing operations and intended: (1) to demonstrate that working conditions, including the levels of individual dose, remain satisfactory; and (2) to meet regulatory requirements. Routine monitoring can be individual monitoring or workplace monitoring. Contrasting terms: task related monitoring and special monitoring. Source Monitoring: The measurement of activity in radioactive materials being released to the environment or of external dose rates due to sources within a facility or activity. Contrasted with environmental monitoring. Special Monitoring: Monitoring designed to investigate a specific situation in the workplace for which insufficient information is available to demonstrate adequate control, by providing detailed information to elucidate any problems and to define future procedures. Special monitoring would normally be undertaken at the commissioning stage of new facilities, following major modifications either to facilities or to procedures, or when operations are being carried out under abnormal circumstances, such as following an accident. Special monitoring can be individual monitoring or workplace monitoring. Contrasting terms: routine monitoring and task related monitoring.Task Related Monitoring: Monitoring in relation to a specific operation, to provide data to support the immediate decisions on the management of the operation. Task related monitoring can be individual monitoring or workplace monitoring. Contrasting terms: routine monitoring and special monitoring. Workplace Monitoring: Monitoring using measurements made in the working environment. Usually contrasted with individual monitoring. (2) Continuous or periodic measurement of radiological or other parameters or determination of the status of a system, structure or component. Sampling may be involved as a preliminary step to measurement. Although the concept is not fundamentally different from (1), this definition is more suited to the types of monitoring concerned primarily with safety (i.e. keeping sources under control) rather than with protection (i.e. controlling exposure). This definition is particularly relevant to monitoring the status of a nuclear installation by tracking plant variables, or monitoring the long term performance of a waste repository by tracking variables such as water fluxes. These examples differ from definition (1) in that the routine measurements are themselves of no particular interest; the monitoring is only to detect unexpected deviations if they occur. Condition Monitoring: Continuous or periodic tests, inspections, measurement or trending of the performance or physical characteristics of structures, systems and components to indicate current or future performance and the potential for failure. Condition monitoring is usually conducted on a non-intrusive basis