ImageVerifierCode 换一换
格式:PPT , 页数:27 ,大小:7.97MB ,
文档编号:4488107      下载积分:22 文币
快捷下载
登录下载
邮箱/手机:
温馨提示:
系统将以此处填写的邮箱或者手机号生成账号和密码,方便再次下载。 如填写123,账号和密码都是123。
支付方式: 支付宝    微信支付   
验证码:   换一换

优惠套餐
 

温馨提示:若手机下载失败,请复制以下地址【https://www.163wenku.com/d-4488107.html】到电脑浏览器->登陆(账号密码均为手机号或邮箱;不要扫码登陆)->重新下载(不再收费)。

已注册用户请登录:
账号:
密码:
验证码:   换一换
  忘记密码?
三方登录: 微信登录  
下载须知

1: 试题类文档的标题没说有答案,则无答案;主观题也可能无答案。PPT的音视频可能无法播放。 请谨慎下单,一旦售出,概不退换。
2: 本站所有资源如无特殊说明,都需要本地电脑安装OFFICE2007和PDF阅读器。
3: 本文为用户(晟晟文业)主动上传,所有收益归该用户。163文库仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对上载内容本身不做任何修改或编辑。 若此文所含内容侵犯了您的版权或隐私,请立即通知163文库(点击联系客服),我们立即给予删除!。
4. 未经权益所有人同意不得将文件中的内容挪作商业或盈利用途。
5. 本站仅提供交流平台,并不能对任何下载内容负责。
6. 下载文件中如有侵权或不适当内容,请与我们联系,我们立即纠正。
7. 本站不保证下载资源的准确性、安全性和完整性, 同时也不承担用户因使用这些下载资源对自己和他人造成任何形式的伤害或损失。

版权提示 | 免责声明

1,本文(核技术医疗应用的辐射安全和防护-gnssn课件.ppt)为本站会员(晟晟文业)主动上传,163文库仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对上载内容本身不做任何修改或编辑。
2,用户下载本文档,所消耗的文币(积分)将全额增加到上传者的账号。
3, 若此文所含内容侵犯了您的版权或隐私,请立即通知163文库(发送邮件至3464097650@qq.com或直接QQ联系客服),我们立即给予删除!

核技术医疗应用的辐射安全和防护-gnssn课件.ppt

1、1Lost Source Accident in NanJing,ChinaBaowei CHEN1),Qipu ZHOU2)1)China Institute for Radiation Protection2)Nuclear and Radiation Safety Center(Affiliated to Chinese Department of the Environment)2Contentsv Sourcev Accident Processv Dose Calculationv Clinical Manifestation SourcevSource:Ir-192vUsage:

2、industrical defect detectionvActivety:about 0.94TBq(25.5Ci)3Process4v On 7th,May Four workers had done industrial defect detection work in a workshop of a factory which locates in NanJing,a big city in the southeast of the China.The work had been finished,the detection instruments needed to be colle

3、cted and taken away from the workshop.5Processv 7th May,about 3:00 a.m.When the workers collected the instruments,they found that the remote control cable cant be unloaded.According to the machines design,only when the radiation source locates in the machine,t h e r e m o t e c a b l e c a n b e unl

4、oaded.Otherwise,the cables unloading is impossible.6 So,the radiation source was suspected still had located in the source guide tube,yet.The workers shook the guide tube wanted to find the source,but there wasnt source in the tube.(Indeed,the source had slid off tube when they had picked the tube u

5、p,before they shook it.)ProcessGuide Tube7Process One worker took a dosimeter to detect the dose near the surface of the machine.The dose rate indication was high,so he thought the source must be located in the machine.(indeed,if there had been a source in the machine,the dose rate near the machine

6、cant be so high.The machines radiation shield is thick enough.The exposure actually came from the radiation source near the machine.)8Process Because the workers believed that the source had located in the machine,they took the machine with the unloaded cable away from the workshop.About at 7:00 a.m

7、.,7th,May Other employees went into the workshop and begun their work.One worker found the source.He picked it up,looked it carefully.He didnt know what it was,then he thrown it out of the workshop.9ProcessAbout at 8:00 a.m.,7th,May Another worker,named Wang(who received the most r a d i a t i o n d

8、 o s e i n t h i s accident),found the source near the workshops door.He thought it was beautiful and attractive,so he picked it and put it into his pocket.Then Wang took a rest with source in his pocket in a rest room about one hour.There was a workmate of Wang in the room,The workmate was also irr

9、adiated.10ProcessAbout at 9:00 a.m.,7th,May Wang had done his normal work till 11:30,some his workmates near him had been irradiated.Wang had finished his work and went his home with the source in his pocket at about 11:30.Then he put the source in a warehouse locates in his backyard.11ProcessAt nig

10、ht,8th,May The formal four workers took the inspection instruments into the workshop again.The film wasnt photo sensitized after the“exposure”.So the radiation source was found lost!12ProcessAt 2:00,9th,May The radiation source lost accident was reported to environment protection bureau and police b

11、ureau of NanJing city.At 3:00,9th,May Environment protection bureaus employees went to the workshop where the source was lost.At 8:00,9th,May The policemen went to the workshop and asked everyone worked in the factory.They promised 20,000 RMB Yuan to the people who provided the corresponding informa

12、tion.But the policemen didnt tell that the lost item is harmful.13Process Mr.Wang felt fearful.He had not the knowledge about radiation source,and he thought the item he had picked up must be very expensive,otherwise the policemen cant provide so much money for its information.He thought policemen m

13、aybe regard him as thief who stolen the“very expensive treasure”.So he didnt tell policemen the truth,and he telephoned his wife to transfer the source to his parents home.Mr.Wang feared and feared at that night.The next morning(10th,May),he went to his parents home,wrapped the source with a dark bl

14、ue plastic bag and thrown it to a grass 100 meters away from his parents home.1415vFinding the source The approximate position of the source was found through gamma-ray detection instruments at morning 9:00 a.m.on 10th May,after Wang had thrown it 3 hours late.But the precise positions determination

15、 was difficult,because the source was too small and the radiation was too strong near the source.Finally,a metal-detector was used to find the precise position of the source.16Process171819Calculation Mr.Wangs DoseLocal DoseLocal Dose:v ThighThigh:D=157Gy (t=3.5h,r=5cm,D5cm=50Gy/h)v Hands Hands:(pic

16、ked up and looked up the source,loaded the source,took the source)D=D1+D2+D3=14.33Gyv Whole Body Dose Whole Body Dose:2.55 Sv(Bladder,gonad,red marrow and skin are mainly considered.)20Calculation Other Peoples DoseWangs Wife:vHands Dose(Carrying source):0.16Gy;vWhole Body Dose(Carrying source and c

17、lose contact source at home):270mSvThe person who first picked up the source:vHands Dose:0.83Gy;vWhole Body Dose:8.3mSv。21Other people working in workshop:9 person(3-5m from source),Dose:2.5-6.25mSv 4 person(6m from source),Dose:1.74mSv 7 person(15m from source),Dose:0.28mSv 20 person(20-40m from so

18、urce),Average Dose:0.07mSvThe road construction workers near the warehouse:20 person(10-20m from source)Dose:0.78 3.125mSv22Calculation Other Peoples DoseThe workmate rested along with Wang in rest room Average range from source:3meters,Dose:13mSvWangs family and tenant:Dose:2537.5mSvWangs parents a

19、nd sister:Wangs Father:0.09mSv;Wangs Mother:1.22mSv Wangs Sister:0.22mSv23Calculation Other Peoples Dose Two tenants lived in second floor up the sources room Dose:5.12-6.4mSv;The constructors near the place where the source was found 11 constructors(30-80m from the source),Maximum Dose:0.42mSv24Cal

20、culation Other Peoples DoseConclude of the calculationvNear 100 people(More than 80)had been irradiated in Near 100 people(More than 80)had been irradiated in this source lost accident.this source lost accident.vThe person who accepted the most dose is Wang.His The person who accepted the most dose

21、is Wang.His local dose are more than 100 Cy,and his whole body local dose are more than 100 Cy,and his whole body dose is about 2.5Sv.This dose is very harmful,but dose is about 2.5Sv.This dose is very harmful,but not fatal.not fatal.vWangs wife had once carried the source and close to Wangs wife ha

22、d once carried the source and close to the source long time at home,her dose maybe about 270 the source long time at home,her dose maybe about 270 mSv.mSv.vAll of the other peoples dose are little than 50mSv.All of the other peoples dose are little than 50mSv.vThese data come from calculation used b

23、y physical These data come from calculation used by physical method,the uncertainties of the data maybe large.method,the uncertainties of the data maybe large.25Clinical Manifestation26 W a n g i s i n t h e hospital and undergoing treatment at present.An abscess had been taken placed on his right thigh.No life threatening temporarily.27ThanksThanks!

侵权处理QQ:3464097650--上传资料QQ:3464097650

【声明】本站为“文档C2C交易模式”,即用户上传的文档直接卖给(下载)用户,本站只是网络空间服务平台,本站所有原创文档下载所得归上传人所有,如您发现上传作品侵犯了您的版权,请立刻联系我们并提供证据,我们将在3个工作日内予以改正。


163文库-Www.163Wenku.Com |网站地图|