Roentgen (unit) Roentgen (unit) The roentgen or röntgen () (symbol R) is a legacy unit of measurement for the exposure of X-rays and gamma rays. It is defined as the electric charge freed by such radiation in a specified volume of air divided by the mass of that air. In 1928 it was the first international measurement quantity for ionising radiation to be defined for radiation protection, and was an easily replicated method of measuring air ionization directly by using an ion chamber. It is named after the German physicist Wilhelm Röntgen, who discovered X-rays. Although relatively easy to measure, it had
Which Medical Device Gerrand and business partner Steve Walmsley. The site incorporates content from the Which Interventional Device website that Dr. Haslam founded in 2007. Which Medical Device currently covers devices in the fields of Interventional Radiology, Cardiology, Orthopaedics and Anaesthesia and Critical care. Which Medical Device Which Medical Device is a review site for medical devices with reviews, medical device news and videos of medical procedures. Users can rate and review medical devices listed on the website, or suggest devices for inclusion and review. The website also publishes device reviews from an editorial team and encourages users to submit detailed reviews. Device