Slide 1:Maykel Chala Administrative and Technical Means Used to Reduce Unnessary Radiation to Patient, Personnel, Self, and Enviroment NMT 2534


Objectives :Objectives List the NRC dose limits Define the ALARA concept Explain Misadministration Describe Misadministration Consequences Discuss methods of reducing radiation to patient Indicate ways to reduce radiation to personnel (Workers) Identify ways of reducing radiation to self (NMT) Analyze methods of reducing radiation to environment


The NRC Dose Limits :The NRC Dose Limits Rem is the unit of dose equivalent for occupational exposure Occupational annual dose limit is 5 rem General public annual dose limit: Frequent –0.1 rem Unfrequent- 0.5 rem Dose to embryo –fetus - 0.5 rem (gestation period of 10 mths)


Definition of ALARA :Definition of ALARA ALARA: As Low As Reasonably Achievable, concept used to minimize personnel exposure from a radioactive source ALARA is based on three principles: Time-minimizing the time of exposure directly Distance: Doubling the distance between your body and the radiation source will divide the radiation exposure by factor of 4 (inverse square law) Shielding: Using absorber materials that will reduce radiation exposure effectively


Time :Time Do not spend more than the necessary time next to a radiation source Minimize the amount of time spent in the vicinity of an operable radiation source Spend the minimum amount of time inside the hot lab while preparing doses


Distance :Distance Increasing the distance between an individual and the source of radiation When the distance is increased the radiation is decreased Maximizing the distance from an operable source of radiation


Shielding :Shielding Shielding is used when the distance or the time it is not effective The degree of exposure reduction will depend on the physical characteristics of the materials between the source of radiation For fixed x ray imaging facilities, the most common materials are lead and concrete


Explaining Misadministration :Explaining Misadministration To ensure that the use of radioactivity is beneficial, procedures must be in place so that the correct patient receives the correct amount of radioactivity for an appropriate study. Examples of misadministration include: Wrong radiopharmaceutical is delivered Wrong patient is treated Wrong route of administration is taken Wrong activity is administered


Explaining Misadministration (Cont’) :Explaining Misadministration (Cont’) If any error is made in dosing a patient, the incident should be documented and the event should be reported to the appropriate regulatory agency immediately Most misadministration result from errors in the Quality Management Program (QMP) It is good practice to investigate the cause and determine possible methods to prevent reoccurrence


Misadministration Consequences :Misadministration Consequences Non justified exposure Increased radiation risk Delayed diagnosis Increased cost Increased workload Reduced confidence


Reducing radiation to patient :Reducing radiation to patient First check patient ID to assure that it is the right patient Doing this ensures that the patient will have the correct study done The NMT should check that the diagnosis corresponds with the study that it is being performed Doing this ensures that the patient will have the correct test images The technician should know that the machine is working correctly before injecting the patient Doing this ensures that the patient it is not exposed to unnecessary radiation because of any malfunction of the machine


Reducing Radiation to Patient (cont’) :Reducing Radiation to Patient (cont’) Prepare the dose with the correct isotope and assay it before giving it to the patient The patient will get the right dose with the right activity These administrative and technical protocols will help prevent the patient from being exposed to unnecessary radiation


Reducing Radiation to Personnel (Workers) :Reducing Radiation to Personnel (Workers) Occupational radiation protection involves various methods of reducing radiation exposure: time, distance, and shielding are the most effective Patients that have been injected with a radioactive isotope should be isolated so personnel working in the area not being exposed to that radiation Radioactive materials should be administered at the location where the studies are performed so radiation does not affect other workers


Reducing Radiation to Personnel (Workers)(cont’) :Reducing Radiation to Personnel (Workers)(cont’) Rooms need to have the wall, door, window, with the correct shielding according to the radioactive material that is going to be used Signs need to be posted at corresponding areas for personnel to know what radiation exposure will occur


Reducing Radiation to Self (NMT) :Reducing Radiation to Self (NMT) It is very important to reduce the exposure to the NMT in the work place since they will be working with radioactive materials for the majority of the time Having the work station properly set up is beneficial because: Equipment at a corresponding distance from each other facilitates easy and direct access The technologist will not exceed the occupational exposure limit while at work by spending unnecessary time


Reducing Radiation to Self (NMT)(cont’) :Reducing Radiation to Self (NMT)(cont’) Surveying the work area minimizes exposure Survey the isotopes that are being shipped to the department daily A technician should be able to perform their duties properly to avoid unnecessary exposure A NMT should always wear protective shielding such as gloves and lab coat when working with radioactive materials


Reducing Radiation to Self (NMT)(cont’) :Reducing Radiation to Self (NMT)(cont’) Wearing a film badge is important because it keeps technicians informed of amount of radiation received High readings may indicate that the tech has done a poor job at minimizing exposure and changes need to be implemented When working with a patient there are different ways to be keep radiation exposure to a minimum: Have all paperwork and information verified before injecting the patient, this will reduce the time spent with the patient while he/she is radioactive


Reducing Radiation to Self (NMT)(cont’) :Reducing Radiation to Self (NMT)(cont’) Patients that are radioactive need to be sitting in a designated area away from the technician while waiting for the procedure


Reducing radiation to environment :Reducing radiation to environment The best way to protect the environment from radiation is to dispose of radioactive materials the correct way they have to be decayed for ten half lives or reach background level Never can be disposed into cold trash Radioactive waste that have long half lives need to be shipped to a designated place where they can be processed Store compatibly with other radioactive materials


Conclusion :Conclusion Various administrative and technical means are used to reduce radiation to patient, personnel, self, and the environment. The NRC sets dose limits to aid in radiation reduction. ALARA is an important concept that incorporates time, distance, and shielding when minimizing exposure. Misadministration ensures that patients receive the correct amount of radioactivity for the appropriate study. Disposing of radioactive materials correctly allows for the protection of the environment


Questions#1 :Questions#1 What is the occupational exposure for a nuclear medicine technologist? a) 5000 rad b)5 sv c)5000 mrem d) b and c Answer : c


Questions#2 :Questions#2 What does ALARA stand for? a) As Low As Radiation Achievable b) As Low As Reachable Achievable c) As Low As Rational Available d)As Low As Reasonably Achievable Answer : d


Questions#3 :Questions#3 Who regulates the dose limits? a)MRC b)NRCP c)ICP d)NRC Answer : d


Questions#4 :Questions#4 Name three consequences of misadministration to a patient Answer: Non justified exposure Increased radiation risk Delayed diagnosis


Questions #5 :Questions #5 What are the three principles of ALARA? a)time, distance, food b)time, radiation activity, shielding c)time, distance, shielding d)time, dose, shielding, distance Answer : c


References :References Christian, Paul E, Donal R Bernier, and James K Langan. Nuclear Medicine and PET. 5th. St . Louis Missouri: Mosby, 2004 Steves, Ann M, and Patricia C Wells. Review of Nuclear Medicine Technology. 3rd ed. Virginia: Society of Nuclear Medicine, 2004.