Paperback. The International Commission on Radiological Protection issued its last basic recommendations in 1977. The recommendations have been used widely throughout the world to limit exposure of both radiation workers and members of the public to ionising radiation. Supplementary statements to the 1977 recommendations were issued when necessary by the Commission, but developments in the last few years have made it necessary to issue a completely new set of recommendations, officially adopted in November 1990. In publishing these recommendations, the Commission has had three aims in mind: to take account of new biological information and of trends in the setting of safety standards; to improve the presentation of the recommendations; and to maintain as much stability in the recommendations as is consistent with the new information. In order to make the 1990 recommendations more accessible to individuals, this Users' Edition contains the main text of th