Roentgen (unit) this derivative quantity the roentgen equivalent physical (rep) to distinguish it from the ICR roentgen. The introduction of the roentgen measurement unit, which relied upon measuring the ionisation of air, replaced earlier less accurate practices that relied on timed exposure, film exposure, or fluorescence. This led the way to setting exposure limits,and the National Council on Radiation Protection and Measurements of the United States established the first formal dose limit in 1931 as 0.1 roentgen per day. The International X-ray and Radium Protection Committee, now known as the International Commission on Radiological Protection (ICRP) soon followed with a limit of
Kevin Roentgen co-produced with Noah Shain a project called Hott Mess, an album of 10 songs written and performed by Roentgen, Shain and singer Shayna Ross. In 2009, Croire en l'homme, was released as the b-side to the debut title track single from Johnny Hallyday's latest album, Ca n'finira jamais. Written by Roentgen and Oliver Leiber, the single debuted at #1 on the French Single Charts, the week of November 14, 2008, and remained number one for two weeks. Later that year, Roentgen produced the Light of Day EP for LA band, Analog Smith. In May 2012, Goldsboro, featuring Roentgen, Chris Cano