Occupational Intakes of Radionuclides Part 1 - ICRP

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DRAFT REPORT FOR CONSULTATION
therefore it is necessary to make some assumptions about the pattern of intakes.
National or local legislation or regulations may also set the requirements for
systematic routine monitoring that may be needed if exposures could exceed a
specified fraction of the dose limit or a dose constraint.
(71) Other monitoring programmes may be conducted in relation to a particular
task, or to determine intakes in actual or suspected abnormal conditions. In these
circumstances, the time of intake, or potential intake, is likely to be known and
workplace monitoring programmes may provide some information on the physical
and chemical nature of any contamination. Special monitoring is performed to
quantify significant exposures following actual or suspected abnormal events.
Confirmatory monitoring is performed where there is a need to check assumptions
made about exposure conditions, for example in order to confirm the effectiveness of
protection measures. Task-related monitoring is carried out for workers engaged on
specific operations.
2.5 Needs for Individual Monitoring
(72) An important function of an employer and/or licensee is that of maintaining
control over sources of exposure and ensuring the protection of workers who are
occupationally exposed. In order to achieve this, the Commission continues to
recommend the classification of controlled and supervised areas (ICRP, 2007). A
controlled area requires consideration of specific protection measures and safety
provisions for controlling normal exposures or preventing the spread of contamination
during normal operations, and preventing or limiting the extent of accidental
exposures. A supervised area is one in which the radiological conditions are kept
under review but special procedures are not normally needed.
(73) It is necessary to identify groups of workers for whom individual monitoring
is needed. The decision to provide individual monitoring depends on many factors.
Routine individual monitoring for intakes of radioactive material should be used for
workers in areas that are designated as controlled areas specifically in relation to the
control of contamination and in which significant intakes cannot be excluded.
(74) Workers in controlled areas are the group who are most often monitored for
radiation exposures incurred in the workplace, and may also receive special medical
surveillance. They should be well informed and specially trained, and form a readily
identifiable group.
(75) The use of individual monitoring for workers whose annual doses could
exceed 1 mSv is common practice in many organisations although it may not be
required by legislation. Regulatory, technical and managerial considerations may
support arguments for the assessment of individual dose at these lower levels, at least
for those radionuclides for which assessment is straightforward and practical.
(76) The following examples indicate the type of operations where experience has
shown that it is necessary to give consideration to routine individual monitoring for
internal exposure of workers:
the handling of large quantities of gaseous and volatile materials, e.g. tritium
and its compounds in large scale production processes, in heavy water reactors
and in luminising;
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