Employee Spotlight: Serendipity and standards brought Frédéric Tessier to the NRC

It’s almost like Frederic Tessier was destined to work at the NRC.

“From a young age, I was captivated by the NRC’s time signal broadcast* by Radio-Canada,” he says. “It sparked my interest in standards.”

Frédéric is a senior research officer at the NRC’s Metrology Research Centre. Metrology is the science of measurement and metrologists are responsible for advancing the precision of physical measurement methods, promoting technological progress and enabling trade agreements. Their work ensures that measurements across Canada are accurate and traceable to a reference standard that is trusted internationally.

After completing his PhD at the 加拿大渥太华大学 , a twist of fate brought Frédéric to the NRC.

“I was on my way to pursuing academic opportunities, but the birth of our first child led us to stay in Ottawa,” he explains. “This decision serendipitously directed my career path to the NRC when the Metrology Research Centre, or the Institute for National Measurement Standards as it was called at the time, posted a job opening for Monte Carlo computer simulations, aligning with my expertise.”

He had studied cell membrane mechanics and DNA sequencing simulations, and his experience in computational physics opened the door to modelling ionizing radiation for dosimetry at the NRC.

Radiation dosimetry research improves the accuracy and precision of measurements of ionizing radiation – the type involved in X-rays, radiation therapy for cancer and even food sterilization processes. A major part of the work Frédéric and his team does is to model radiation detectors.

Frédéric is the newly appointed Team Lead for Medical and Industrial Dosimetry at the Metrology Research Centre. His work involves creating 3D models of radiation generators and detectors, such as X-Ray tubes used by dentists or ionization chambers used to quantify the amount of radiation that is emitted by a device. Using computers, he simulates how energetic particles interact with the equipment. While he handles virtual experiments, his colleagues conduct corresponding experiments in labs.

The collaboration allows the group to continuously improve the accuracy of existing radiation detectors for protection and medical applications, in addition to crafting new ones. As Canada’s national measurement laboratory, the Metrology Research Centre is responsible developing and disseminating accurate measurement standards the International System of Units (SI), in this case the Gray (Gy), the unit of absorbed radiation dose.

“Radiation is a tough quantity to track, because it travels at or near the speed of light, it is invisible and it can be dangerous,” he explains. “My team’s job is to ensure that radiation detectors are accurate. This in turn allows cancer clinics, for example, to calibrate their machines every day to ensure patients receive the right amount of radiation to eradicate cancerous tumours while sparing healthy tissue.”

His simulation team also works to enhance the NRC’s electron gamma shower software, more commonly known as EGSnrc, which models the passage of radiation in matter. It’s a leading global toolkit continuously developed at the NRC over the last 40 years, and distributed openly.? It is widely used in radiation therapy and medical imaging. But as a generic simulation software for radiation transport, it is also used across industries where radiation is relevant, from electronic microscopy to atmospheric science, and even space exploration.

In addition to his work at the Metrology Research Centre, Frédéric actively manages and supports the release of Open-Source Software by NRC researchers on Github, to promote transparency and collaboration. He and his colleagues also occasionally teach ionizing radiation modelling in universities, government laboratories, and under the sponsorship of the International Atomic Energy Agency to train medical physicists from developing countries.

Frédéric also recently accepted a one-year term as President of the Council on Ionizing Radiation Measurements and Standards . It’s an independent, non-profit and cross-industry council that aims to engage academic, industrial and regulatory bodies to stimulate research in ionizing radiation metrology.

“I am grateful for how life's twists and turns brought me to the NRC,” he says. “Not only have I found professional fulfilment, but also a great community of colleagues.”

* As of October 10, 2023, the time signal is no longer broadcast on CBC/SRC but Canada’s Official Time can still be accessed through the NRC Web Clock or by calling 613-745-1576.

To learn more about the contributions of many of the talented people that make up the NRC, visit our stories webpage.