Much Effort; Little Energy by Jeremy Whitlock The Chalk River Branch of the Canadian Nuclear Society welcomed guest speaker Richard Osborne on Thursday, March 11 at the J.L. Gray Centre. Dr. Osborne, a local resident and world expert on radiation protection, retired last year from AECL. His legacy to the science of tritium dosimetry was the feature of his presentation, entitled "Much Effort; Little Energy". That title refers to the years of research devoted at AECL to tritium, a form of hydrogen with very low-energy radioactivity. Tritium is of particular interest to the nuclear industry since it is produced abundantly in heavy-water reactors like CANDU, as well as NRX and NRU at Chalk River. If taken into the body the low-energy radiation of tritium can be hazardous, although it is relatively harmless externally. A common pathway into the human body occurs when tritium forms part of an ordinary water molecule. Comprising 60% of our body mass, water is an efficient "Trojan horse" for the tritium isotope. Consequently, the uptake of tritium by this method, especially in the workplace, was a major concern in 1963 when Dr. Osborne came to AECL. At that time Dr. Osborne had started to make a name for himself in the field of radiation biophysics, with a PhD from London University a year earlier. Over the next two decades he would lead the tritium program at AECL, studying not only the various pathways that "tritiated" water and water vapour can enter the body, but also new methods for detecting tritium in the workplace. In his early years at AECL Dr. Osborne made ample use of volunteers for such exposure studies, but the lab subject he exploited the most was probably himself. His experimentation on himself and others is probably as amusing today as it is resistant to regulator approval. Along the way Dr. Osborne saw several successes and several blind alleys. He is proud of the portable tritium monitors which he helped develop, and which are now one of the more successful instruments marketed by Scintrex. He notes that the yellow colour of the commercial product comes from the hue of the early Black & Decker power-tool hand grips, which formed part of the prototype. Dr. Osborne also points to the many successful non-portable tritium detectors created at Chalk River and installed at CANDU plants, but made a strong point about the lack of a local "champion" at the sites often leading to misuse and neglect of these sometimes finicky tools. He is proud of the newer, more robust products that partly address this problem, and which Chalk River still takes a lead role in developing. If the "little energy" of Dr. Osborne's title is a universal constant, then the "much effort" is clearly, for the time being at least, continuing at Chalk River. Richard Osborne remains in Deep River, and remains an active participant on international committees and advisory groups monitoring and attempting to improve the state of radiation protection globally.