Ionizing radiation members, to comply with a European Directive. The FAA has a recommended limit of 1 mSv total for a pregnancy, and no more than 0.5 mSv per month. Information originally based on "Fundamentals of Aerospace Medicine" published in 2008. Hazardous levels of ionizing radiation are signified by the trefoil sign on a yellow background. These are usually posted at the boundary of a radiation controlled area or in any place where radiation levels are significantly above background due to human intervention. The red ionizing radiation warning symbol (ISO 21482) was launched in 2007, and is intended for IAEA Category 1,
Ionizing radiation Despite the high levels of background radiation that the residents of Ramsar receive there is no compelling evidence that they experience a greater health risks. The ICRP recommendations are conservative limits and may represent an over representation of the actual health risk. Generally radiation safety organization recommend the most conservative limits assuming it is best to err on the side of caution. This level of caution is appropriate but should not be used to create fear about background radiation danger. Radiation danger from background radiation may be a serious threat but is more likely a small overall risk compared to