Speaker
Description
Following a radiological incident, there is a need to rapidly monitor a range of sample types for multiple radionuclides to assess the risks to the public and the environment. Such rapid measurements will also be beneficial for high throughput routine monitoring of samples in and around nuclear sites.
This study describes the recent developments and comparison of methods for measurement of actinides (Th, U, Pu, Np, Am) following a radiological incident. This contributes to meeting the requirements of the European Metrology Research Programme project Preparedness (2017-2021). The project focused on air filter samples, which were initially treated using microwave digestion. Sample digests were split into two fractions. One half was measured directly by tandem inductively coupled plasma mass spectrometry (ICP-MS/MS) without further treatment. The instruments integrated reaction cell and two quadrupole mass filters were used for online removal of interferences, such as 238U tailing and 238U1H polyatomic overlap on 239Pu. The second half of the samples were taken through a single stage extraction chromatography separation procedure to isolate each actinide prior to measurement using alpha spectrometry. Suitable tracers were added to assess the chemical recovery, and a fraction of each separated fraction was taken for ICP-MS/MS measurement to check the agreement between the two techniques.
Data is presented to show the difference in measurement, procedural and analyst time, as well as the detection limits achievable and number of samples that can be measured within a single batch. The results have implications for deciding on the measurement route required depending on the analyte(s), turnaround time and limit of detection required.