A simple method for assessing exposure to internal emitters

One of the most challenging aspects of regulatory compliance can be demonstrating compliance with internal dosimetry requirements. For long-lived alpha-emitting radionuclides in particular, the sensitivity and accuracy of bioassay analysis and whole body counting may not allow for adequate assessment of intakes. Simple and effective measures can be used to control the workplace for the internal hazards associated with long-lived radioactive material using methods that measure directly the air to which workers are exposed. This paper provides an easy assessment tool that uses direct measurement of the specific activity of dusts in breathing zone air to evaluate internal exposures. Using this method, sensitive assessments can be made to determine if intakes are likely to have occurred and, if so, at what magnitude. It is not a substitute for confirmatory bioassay or whole body counting but a simple method to evaluate expectations for internal exposures.