Roentgen equivalent man has been defined since 1976 as equal to 0.01 sievert, which is the more commonly used SI unit outside the United States. A number of earlier definitions going back to 1945 were derived from the roentgen unit, which was named after Wilhelm Röntgen, a German scientist who discovered X-rays. The acronym is now a misleading historical artifact, since 1 roentgen actually deposits about 0.96 rem in soft biological tissue, when all weighting factors equal unity. Older units of rem following other definitions are up to 17% smaller than the modern rem. One rem carries with it a 0.05% chance of
Abraham Roentgen he established a furniture manufactory. Upon his retirement in 1772 his son David took over the business and established his own reputation. Abraham Roentgen died in Herrnhut in Saxony Germany in 1793. Abraham Roentgen Abraham Roentgen (30 January 1711 – 1 March 1793) was a German Ébéniste (cabinetmaker). Roentgen was born in Mülheim am Rhein, Germany. He learned cabinet making from his father. At age 20, he traveled to Den Haag, Rotterdam and Amsterdam, learning from established cabinet makers. He became known for his marquetry work, and worked in London (in the workshop of William Gomm) until 1738. On 18