版权说明:本文档由用户提供并上传,收益归属内容提供方,若内容存在侵权,请进行举报或认领
文档简介
1、Safety (5%) 2 Safety (A-E = 4%= 8 Questions, F-G = 1%= 2 Questions) A. Infection Control B. Sterile Technique C. Radiation Physics / Safety D. Electrical Safety E. Drug Interaction F. Device Interaction G. Recalls and Advisories 3 Infection Control & Sterile Technique 1. Chain of infection - Infecti
2、ous agent eg: Bateria, Fungi - Susceptible host eg: Elderly - Means of transmission eg: Contact, Airborne 2. Methods of interruption of chain of infections - Destruction of infectious agent Heat sterilization (steam, hot air) Ethylene oxide gas sterilization Chemical sterilization (Glutaraldehyde/ f
3、ormaldehyde) - Reduction of host susceptibility - Interruption of transmission Strict sterile technique intraprocedure Isolation of incision site from environment 3. Maintenance of Sterility Intraprocedure - Sterile drape integrity - Traffic control within room - Sterile occlusive dressing 4 Infecti
4、on Control & Sterile Technique Radiation Safety Exposure to X-rays is a cumulative effect Types of radiation - Non-ionizing Radiation Electromagnetic waves given off by the sun Various electronic devices Example UV light, Infrared radiation, RF radiation Microwaves Does not have enough energy to cau
5、se ionization of atoms 5 Radiation Safety Ionizing Radiation - By the sun - By radioactive materials - By high energy electronic devices ( X-ray machines) - Has enough energy to cause atoms to lose electrons and become ions or charged atoms. - Example / particles Gamma rays X-rays 6 Radiation Safety
6、 Characteristics of Ionizing Radiation Inversely proportional to the distance from the energy source The further you move away from the source of radiation, exposure is decreased by the square of the distance Since X-rays have no charge, they cannot be bent Travel in a linear path Damage at the cell
7、ular level is irreparable and irreversible If male of female germ cells or gametes (egg or sperm) have been affected, the damage could be inherited in the next generation. 7 Radiation Safety EXPOSURE If exposure time is doubled, the doses will be doubled. Exposure = Exposure rate x Time. Exposure is
8、 a measure of source intensity x time. Exposure rate is measured in milliroentgens(mR). Example- A radiation source has an exposure rate of 225 mR/hr at a position occupied by a radiation worker. If the worker remains at that position for 36 minutes, what will be the total occupational exposure? Ans
9、wer: Occupational exposure = (225mR/hr) * (36min/60min/hr) = 135mR 8 Radiation Safety DISTANCE As distance between the source of radiation and a person increases, the exposure decreases rapidly. This can be calculated by the inverse square law. - Inverse square law: ( I1/ I2 ) = (d2 /d1) Example Wit
10、h an exposure rate of 0.5mR/hr at 5 ft. = 0.125 mR/hr at distance of 10ft. 2 Formula: 0.5mR(5/10) = 0.5mR(0.25) = 0.125mR 9 Radiation Safety Rad (Radiation absorbed dose) - A unit of absorbed dose. - One rad is 0.01 Joule absorbed per kilogram of any material - Being replaced by the gray (Gy) - One
11、rad equals one hundredth of a gray REM - Roentgen Equivalent Man - The unit of dose equivalent or occupational exposure - Express radiation quantity received by radiation workers ( 1 rem equals to 1.07185 rntgen). 10 Radiation Safety Scatter Radiation Formula - no exact formula to calculate scatter
12、- “rule of thumb” does exist in that the scatter at 1 meter from patient center field is approximately 0.1% of primary beam dose rate at 1 meter from center beam Example If the exposure rate in the center of a primary beam were 1 R/min, the scattered exposure rate would be 0.1 R/min. at 1 meter from
13、 that point. The inverse square law does apply here. 11 Review Questions 1.The output intensity of a radiographic unit is 4.2 mR/mAs. What is the total output following a 200ms exposure at 300mA? Ans: 4.2mR/1mAs = x/60mAs x=252mR 2.What is the approximate patient skin dose following a 3.2-minute flu
14、oroscopic examination of 1.5 mA? Ans: Exposure= (ExposureRate)(time) (1.5mA)(3.2min)= xmAs (1.5mA)(192s)=288mAs 3.At 60 cm from the side of a fluoroscopic table (assume 90 cm from a point source) the exposure rate is 50mR/hr. What is the exposure rate at 180 cm from the source? Ans: I1/I2=(d2/d1) 2
15、50mr/hr/x=(180/190) 2 50mr/hr = x(2) x=12.5 mr/hr. 12 4.If an individual remained 30 cm from the table (60 from the source) for a total of 150 minutes of beam-on time during a week, what would be the expected personnel exposure? Ans: I1/I2 = (d2/d1) 50mr/hr /x = (60/90) 50mr/hr = x (.444) x = 112.5
16、mr/hr (112.5 mR/hr) (150min) (1hr/60min) = 112.5mR/hr (2.5hr) = 281.25mR 13 5.What exposure will an individual receive when exposed for ten minutes at 4m to a source with intensity of 100mR/hr at 1m while wearing a protective apron equivalent to 2 HVLs? Ans: 100mR/x= (4/1) = 6.25 mR/hr 2 (6.25mR/hr)
17、(10min) (1hr/60min) /2 2 = 1.0416662/2 = .2604 6.The exposure from an X-ray tube operated at 70kVp, 200 mAs is 400 mR at 36 in. What will be the exposure rate at 72 in? Ans: I1/I2 = (d2/d1) 2 I1 = I2(d2/d1) 2 I1 = 400mR (36in/72in) I1 = 400 mR(1/4) I1 = 100 mR 14 7.A radiographic unit shows patient
18、skin dose to be 5.4mR/mAs at 70Kvp. What will be the appropriate rate at 72 in? Ans: I1/I2 = mAs1/mAs2(Kvp1/Kvp2) 2 x/5.4 mR/mAs= 120mAs/1(84/70) 2 x/5.4 mR/mAs= 120 mAs (1.2) x = (5.4mR/mAs) (120 mAs) (1.44) x = 933.12 mR/mAs 15 Radiation Safety 1. Equipment safety a)Inspected at intervals recommen
19、ded by state/federal guidelines b)Maintain ongoing preventive maintenance as per institutional/ governmental requirements c)Complete repairs promptly d)Use appropriate cords, cables, and grounding e)Complete calibration/inspection/certification on new equipment prior to use f)Post appropriate signag
20、e in areas where X-ray is used. 2. Exposure levels for non-occupationally exposed workers = workers with the potential to receive greater doses must wear a radiation badge. 1) 500mrem/year 2) 125mrem/year 16 Radiation Safety cont 3. Radiation field a) Minimize time and dose b) Decrease time in and a
21、round radiation field c) Increase distance from radiation field double the distance to decrease dose by a factor of 4 d) Increase shielding between personnel and the radiation source soft tissue as well as lead attenuates ionizing radiation. 4. Lower room lights during procedure less fluoroscopy tim
22、e needed 17 Radiation Safety cont 5. Tube placement a) Place image intensifier close to patient to reduce irradiated field size and “scatter” b) Raising image intensifier from patient reduces radiation dose to patient 6. Collimate system to area of interest only reduces field size and scatter 7. Mov
23、e monitor close to viewing personnel reduces time required for study 8. Always record fluoroscopy time and exam- allows for more accurate dosimetry 18 Always Evaluate device after the end of procedure Electro- cautory MRIRFLithotri- psy DF shock Radiation Therapy Possible effects -Reprogramming -Noi
24、se reversion -Transient inappropriate inhibition or triggering -Transient alternation in capture or sensing thresholds - do - - do - - do - - do - do - do Transient malfunction - do - do - - do - - do - Precau- tions -Low energy setting -Bipolar cautery -Ground placement -minimize current path Avoid procedure Inactivate if ppm not dependant Distance 8- 10cm Distance the paddle placement Distance shielding Relocation of Device 19 Device Interaction Other Devices Interaction Arc welders Diathermy Tr
温馨提示
- 1. 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。图纸软件为CAD,CAXA,PROE,UG,SolidWorks等.压缩文件请下载最新的WinRAR软件解压。
- 2. 本站的文档不包含任何第三方提供的附件图纸等,如果需要附件,请联系上传者。文件的所有权益归上传用户所有。
- 3. 本站RAR压缩包中若带图纸,网页内容里面会有图纸预览,若没有图纸预览就没有图纸。
- 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. 人人文库网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,对用户上传分享的文档内容本身不做任何修改或编辑,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。
最新文档
- 2024年凌海市一级造价工程师《土建计量》点睛提分卷含解析
- 2024围墙承包合同协议书
- 2024年金属门窗及类似制品项目合作计划书
- 2024商铺租赁合同书范本
- 2024年密封垫及类似接合衬垫项目建议书
- 2024年三元催化净化器项目合作计划书
- 2024年酯类项目发展计划
- 2024年双道氢化物发生原子荧光光度计项目合作计划书
- 2024年气体分析仪项目发展计划
- DB4101-T 99-2024 食品检验检测实验室废弃样品管理规范
- 山东工艺美术学院课程建设质量评估指标体系
- 新译林版六年级上册英语知识点归纳总结
- 危险废物贮存设施标识(示例)
- 专职消防员心理测试题目
- 钢笔字帖楷体常用汉字2500个(米字格实笔画)15338
- 照明亮化方案(课堂PPT)
- 锚索肋板式挡墙护坡实施施工方案
- 高速公路边坡钢板桩支护施工方案
- 硬笔书法田字格纸张
- 律师服务质量监督和反馈表(共1页)
- 塞戈维亚音阶练习指导
评论
0/150
提交评论