ISO 16639:2017 pdf free.Surveillance of the activity concentrations of airborne radioactive
substances in the workplace of nuclear facilities.
Air sampling techniques consist of two general approaches. The first approach is retrospective sampling, in which the air is sampled, the collection medium is removed and taken to a radiation detector system and analysed for radioactive substance, and the concentration results made available at a later time. In this context, the measured air concentrations are evaluated retrospectively. The second approach is continuous real-time air monitoring so that workers can be warned that a significant release of airborne radioactivity may have just occurred. In implementing an effective air sampling program, it is important to achieve a balance between the two general approaches. The specific balance depends on hazard level of the work and the characteristics of each facility.
A special component of the second approach which can apply, if properly implemented, is the preparation of continuous air monitoring instrumentation and protocols. This enables radiation protection monitoring of personnel that have been trained and fitted with personal protective equipment (PPE) that permit pre-planned, defined, extended stay time in elevated concentrations of airborne radioactive substances. Such approaches can occur either as part of a planned re-entry of a contaminated area following an accidental loss of containment for accident assessment and recovery, or part of a project which involves systematic or routine access to radioactive substances (e.g. preparing process material containing easily aerosolized components), or handling objects such as poorly characterized waste materials that may contain radioactive contaminants that could be aerosolized when handled during repackaging. In this special case, the role of continuous air monitoring is to provide an alert to health physics personnel that the air concentrations of concern have exceeded a threshold such that the planned level of protection afforded by PPE has been or could be exceeded. This level would typically be many 10’s or 10 0’s of times higher than the derived air concentration (DAC) established for unprotected workers. The monitoring alarm or alert would therefore be designed not to be confused with the normal monitoring alarm, and the action taken in response would be similarly targeted at the specific site and personnel involved.
The air sampling strategy should be designed to minimize internal exposures and balanced with social, technical, economic, practical, and public policy considerations that are associated with the use of the radioactive substance.
A comprehensive air sampling strategy should also consider that the air sampling program is only one element of a broader radiation protection program. Therefore, individuals involved with the air sampling program should interact with personnel working in other elements of the radiation protection program, such as contamination control and internal dosimetry.
This document does not address outdoor air sampling, effluent monitoring, or radon measurements.A special component of the second approach which can apply, if properly implemented, is the preparation of continuous air monitoring instrumentation and protocols which enable radiation protection monitoring of personnel that have been trained and are using PPE that permit pre-planned, defined, extended stay time in elevated concentrations of airborne radioactive substances. Such applications can occur either as part of a planned re-entry of a contaminated area following an accidental loss of containment for accident assessment and recovery, or part of a project which involves systematic or routine access to radioactive substances (e.g. preparing process material containing easily aerosolized components), or handling objects such as poorly characterized waste materials that may contain radioactive contaminants that could be aerosolized when handled during repackaging. In this special case, the role of continuous air monitoring is to provide an alert to health physics personnel that the air concentration(s) of concern have exceeded a threshold such that the planned level of protection afforded by PPE has been or could be exceeded. This level would typically be 10’s or 100’s of DAC. The monitoring alarm or alert would therefore be designed not to be confused with the normal monitoring alarm, and the action taken in response would be similarly targeted at the specific site and personnel involved.ISO 16639 pdf download.