核技术医疗应用的辐射安全和防护.ppt

* * * * * * * * * * * * * The radiological accident in Goiania, Brazil is well documented. The IAEA published an extensive report on this accident: INTERNATIONAL ATOMIC ENERGY AGENCY, The Radiological Accident in Goiania, IAEA Report, IAEA, Vienna (1988). Basic information, data and photos in this module are taken from this report. This photo shows the extent of the remedial work that had to be undertaken, in this case the demolition of a contaminated house. It illustrates the severity of the event. * The former premises of a private radiography institute were partly demolished. Photo: The derelict radiotherapy clinic in Goiania from which the caesium source was taken. * IGR = name of clinic Note lack of responsibility for / supervision of the source after closure of clinic. * Note large amount of lead in source head - high value scrap * CsCl: highly soluble; easily spread easily absorbed in the body. * This and next 3 slides: Describe events leading up to discovery of the incident Include dose rates where relevant * * * Describe ‘hunch’ by Junkyard manager’s wife leading to transport of source remnants to hospital by bus. Describe identification of radiation by visiting medical physicist. * Photo Monitoring people for contamination at the Olympic stadium. * Describe causal factors: Lack of supervision by clinic owner chemical form of source Describe lessons learnt * Photo A hole is made to remove a radiation hot spot giving dose rate of 0.5 Sv/h. * Photo Removing contaminated items from junkyard. * Photo Waste containers at the temporary storage site. * * * * * * * * * 个人剂量计 采用多个 个人剂量计 From: Avoidance of radiation injuries from interventional procedures. ICRP draft 2000 * 铅屏 甲状腺护套 铅围裙和 铅眼镜 * 谢谢！ * * 见P31 * 详细资料：每年天然辐射中：1.81mSv---------年当量剂量中各辐射来源的比重（宇宙射线0.28mSv；原生放射性核素1.0mSv；陆地辐射0.26mSv；宇生放射性核素0.01mSv； * * * * “Stationary” in comparison to a “rotating” anode x-ray tube. Typical of early x-ray tubes but can have severe limitations on loa