Reducing radiation exposures to levels that are "as low as practicable" (ALAP) or "as low as reasonably achievable" (ALARA) has long been the goal of the radiation protection programs of the U.S. Department of Energy (DOE), its predecessor agencies, and contractor organizations. The concept had its roots in the Manhattan District where, as early as 1944, the Director of the , Health Division noted that the only safe practice for internal emitters was to avoid intake. By 1946, the ALARA philosophy had been incorporated into the radiation safety manual for the laboratory that would later become Oak Ridge National Laboratory (ORNL), and ALARA was conceptually introduced and published in 1954 into the recommendations of the National Committee on Radiation Protection, now the National Counci 1 on Radiation Protection and Measurements (NCRP). In 1959, the first pub1 ication of the International Commission on Radiological Protection (ICRP) used the phrase "as low as practicable." Since 1954, the basic policy of DOE and its predecessor organizations, the Atomic Energy Commission (AEC) and the Energy Research and Development Administration (ERDA) , has been to follow applicable guidance from the Federal Radiation Council (FRC) , NCRP, and ICRP. As early as 1960, the AEC stated in its orders that "...human exposure to ionizing radiation shall be kept as low as practicable." In 1975, requirements for keeping radiation exposures as low as practicable were introduced in ERDA Manual Chapter 0524. In 1981, these requirements were included in the most recent DOE Order 5480.1, Chapter XI, and were continued in the 1988 draft revised DOE Order 5480.11. These requirements represent the formalization of a position long held and practiced by DOE and its contractors and, as such, are not a new philosophy or commitment. Although the phrase "as low as practicable" has, in recent years, been supplemented by "as low as (is) reasonably achievable," the basic concept has not changed. Indeed, although some argue that subtle differences exist between the two phrases as applied to radiation protection, ALAP and ALARA are identical in intent and may be used interchangeably. In addition, the term "optimization" was defined by the ICRP to be identical with ALAP and ALARA. Section 2.0, Administration, discusses the essential systems and tools available to management for implementing and controlling an ALARA program. This section emphasizes the value of strong management commitment and support, formal and informal communications systems, effective education and training programs in support of the program, and routine internal and external audits and appraisals of the implementation and function of the program. To ensure accountability for conduct of the ALARA program, management should delegate specific responsi bi 1 i ties and provide fol low-up. Section 3.0, Optimization, has been added to the revised manual because, in recent years, the importance of including optimization techniques in an ALARA program has greatly increased. It is now necessary...