Challenges and solutions to low count rate in-field situations.

Challenges and solutions to low count rate in-field situations.

Presented by: Dean Crouch, Resources Health & Safety Services

Time: 1pm AEST (11am AWST)

PRESENTER BIO

Dean has been in the radiation safety field for 20+ years, working in nuclear medicine, mining, oil, and gas. He has also been a WA Mines Inspector. He is a member of the Australasian Radiation Protection Society (ARPS), the Australian Institute of Occupational Hygiene (AIOH), and the Registrar and board member of the Australasian Radiation Protection Accreditation Board (ARPAB).
In these roles, Dean has developed and implemented site- or equipment-specific methodologies for measuring the impact of low and near-background contamination levels and the challenges of providing quantitative results.

ABSTRACT

Portable radiation measuring equipment, a field that has evolved since the original ion chambers during early studies of X-rays (Flakus 1981), has always been a balance between detection efficiency and practicality. The industrial uses of radiation, mostly involving high-activity sources or output X-ray tubes, have led to the development of survey meters with smaller detectors and more robust designs, making them the most common devices for in-field radiation inspections.

As radiation impacts non-human biota and environmental radiation measurements become more common, these industrial survey meters are only partially suitable for this purpose. To be of actual value, the operator must know the principles of counting statistics and how the survey meter uses this to determine a final result. The process is rarely as simple as pointing the survey meter at the ground and reading the display.

This presentation will cover basic radiation physics and counting statistics in a survey of in-field low radiation levels. It will then give examples of how these statistics can cause measurements to be wrong or not provide answers without significant uncertainty and methods to correct these issues.

The presentation will focus on the mining industry, but the physics and methods apply low count rate or poor signal-to-noise measurement.