Annual Dose: The dose due to external exposure in a year plus the committed dose from intakes of radionuclides in that year. The individual dose, unless otherwise stated. This is not, in general, the same as the dose actually delivered during the year in question, which would include doses from radionuclides remaining in the body from intakes in previous years, and would exclude doses delivered in future years from intakes of radionuclides during the year in question. Avertable Dose: The dose that could be averted if a countermeasure or set of countermeasures were to be applied. Averted Dose: The dose prevented by the application of a countermeasure or set of countermeasures, i.e. the difference between the projected dose if the countermeasure(s) had not been applied and the actual projected dose. Collective Dose: The total radiation dose incurred by a population. This is the sum of all of the individual doses to members of the population. If the doses continue for longer than a year, then the annual individual doses must also be integrated over time. Unless otherwise specified, the time over which the dose is integrated is infinite; if a finite upper limit is applied to the time integration, the collective dose is described as  truncated at that time. Unless otherwise specified, the relevant dose is normally effective dose (See collective effective dose for the formal definition). Unit: man sievert (man Sv). This is, strictly, just a sievert, but the unit man sievert is used to distinguish the collective dose from the individual dose which a dosimeter would measure (just as, for example, man hours are used to measure the total effort devoted to a task, as opposed to the elapsed time that would be shown by a clock). Contrasting term: individual dose. Committed Dose: The lifetime dose expected to result from an intake. This term partially supersedes dose commitment