As a key component of integrated Source Term Monitoring (iSTM), Outage Activity Transport Monitoring (OATM) entails the collection of data through in-situ gamma spectroscopy and dose rate measurements, followed by interpretation of data. This establishes the location, type (distributed or localized deposit), composition, and specific activity of radioisotopes within a reactor component or system.

Typically, OATM surveys focus on the Primary Heat Transport (PHT) system, including the reactor vault, reactor face, steam generators and heat exchangers, as well as the feeder cabinets.

We were responsible for summarizing the OATM process in a guideline for CANDU plants and developing a methodology for collecting and analyzing the radiation field and gamma spectral data in a consistent way. During reactor outages, we routinely perform gamma field characterizations of reactor components to determine the radionuclide distribution of deposits in the PHT system and to establish trends.

The OATM surveys give a spatial distribution of the radiation field in the reactor vault at various elevations and distances from the reactor face. The OATM data is also used for trending analysis and optimization of radiation protection.

Why Us?

  • Helping you Optimize Radiation Protection

    We measure radiation during outages to create reactor face dose rate maps and gamma field distributions in the vault. Non-uniformities in the radiation fields are further analyzed to fully understand the activity deposition pathways.

  • Systematic OATM Survey Methodology

    By establishing a methodology for systematically and consistently collecting and analyzing data we are able to trend and develop inter-comparisons of outage gamma fields and radionuclide activities.

  • Reliable Data

    Gamma spectral data is used to estimate the absolute specific activity of individual radionuclides deposited on the primary heat transport system components using established and validated radiation models.

  • Specialized Equipment

    Because we are regularly and frequently undertaking OATM projects we have built up a comprehensive set of reliable monitoring instruments that will provide consistent and reliable results.

  • Manage the Causes of Build-up

    Knowing the pathways allows you to establish and manage the causes of radioactivity build-up and to optimize radiation protection.

  • Manage Personnel Doses

    The OATM data provides you with the reliable data you need to effectively and safely manage performance and personnel doses.