Made with Xara Talk to us and ask the expert  Welcome to Operational Radiation Safety “Πάν μέτρον άριστον” Radiation doses to people from human activities can arise during normal planned operations or can arise from accidents. People working with radioactive  materials or in facilities where radiation is present can receive doses from handling and processing radioactive materials or from the presence of radioactive  materials within the workplace. Members of the public can receive doses from effluent discharges with some levels of radioactivity, from materials released  from nuclear facilities, from the transport of radioactive material to and from the facilities, and from the management of radioactive waste. Such doses can be  as a result of direct external exposure to the radiation associated with the radioactive material, or from internal exposure due to intakes of radionuclides in  air, foodstuff and water. Radiation doses to people can also arise from accidents in which control is lost over a radiation source within a facility or in which  radioactive material is released to the environment. Such releases can be airborne or through water pathways. Airborne releases can be gaseous, particulate  or volatile material. Accidental releases generally take place over short periods lasting hours to days, they take place often without warning or after some time  into the evolution of an accident.  The annual doses in millisieverts (mSv) due to natural sources of radiation are summarized below: