8 Radioactive Materials Safety Manual Environmental Health and Safety A Introduction Radioactive materials and radiation producing devices have long been used as important tools in research and teaching. Concern over health risks associated with radiation exposure has led to occupational exposure limits and strict regulatory controls governing the possession and use of all sources of ionizing radiation. Current radiation exposure limits are based upon the conservative assumption that there is no completely safe level of exposure. This assumption has led to the general philosophy and regulatory requirement of not only keeping exposures below recommended levels or regulatory limits, but of also maintaining all exposures ALARA. This is a fundamental tenet of current radiation safety practice. In order to ensure that all users of ionizing radiation at ISU are in compliance with existing regulatory requirements, and that radiation exposures are maintained ALARA, EH&S has implemented the policies and procedures contained in this Radioactive Materials Safety Manual. This manual is intended to provide sufficient information to ensure that radiation safety practices at ISU are of the highest quality. It is the responsibility of each person working with RAM to become familiar with the contents of this manual and to observe those procedures and requirements contained herein that are applicable to their work. This manual is intended to supplement the requirements found in the ISU Laboratory Safety Manual. For individuals seeking initial authorization approval to use RAM at ISU, a detailed list of the necessary steps for obtaining approval and initiating the use of RAM has been prepared and can be found on the EH&S website.