Part 12 IAEA Training Material on Radiation Protection in Nuclear Medicine Protection of the General Public

Part 12Part 12

IAEA Training Material on Radiation Protection in Nuclear Medicine

Protection of the Protection of the General PublicGeneral Public

Part 12. Protection of the general public 2Nuclear Medicine

ObjectiveObjective

To become aware of the BSS requirements To become aware of the BSS requirements for the protection of the public and how these for the protection of the public and how these are applied to restrictions in the care of the are applied to restrictions in the care of the nuclear medicine patients as well as the nuclear medicine patients as well as the design and operation of a nuclear medicine design and operation of a nuclear medicine facility facility


ContentContent

Dose limitsDose limits Design considerationsDesign considerations The patientThe patient Special problemsSpecial problems TransportationTransportation


Exposure of the general publicExposure of the general public

Spread of contamination outside the Spread of contamination outside the departmentdepartment

Lost sourcesLost sources The nuclear medicine patientThe nuclear medicine patient Disposal of radioactive wasteDisposal of radioactive waste Transportation of sourcesTransportation of sources


RESPONSIBILITIESRESPONSIBILITIES

BSS III.1. BSS III.1. Registrants and licensees shall Registrants and licensees shall apply the requirements of the Standards as apply the requirements of the Standards as specified by the Regulatory Authority to any specified by the Regulatory Authority to any public exposure delivered by a practice or source public exposure delivered by a practice or source for which they are responsible, unless the for which they are responsible, unless the exposure is excluded from the Standards or the exposure is excluded from the Standards or the practice or source delivering the exposure is practice or source delivering the exposure is exempted from the requirements of the exempted from the requirements of the Standards. Standards.


Part 12 Part 12 Protection of the General PublicProtection of the General Public

Module 12.1. Dose limitsModule 12.1. Dose limits


Summary of dose limits established in the Basic Safety Standards.

DOSE LIMIT (1)

APPLICATION

Occupational

Public

Effective dose 20 mSv per year averaged over defined periods of 5 years (2)

1 mSv per year (3)

Effective dose to the embryo or foetus

1 mSv The embryo or foetus is afforded the same broad level of protection as required for members of the public.

Annual equivalent dose in the lens of the eye the skin (4) the hands and feet

150 mSv 500 mSv 500 mSv

15 mSv 50 mSv

1. 2. 3. 4.

The limits apply to the sum of the relevant doses from external exposure in the specified period and the 50-year committed dose (to age 70 years for children) from intakes of radioactive nuclides in the same period With the further provision that the effective dose should not exceed 50 mSv in any single year. In special circumstances a higher value of effective dose could be allowed in a single year, provided that the average over 5 years does not exceed 1 mSv per year. The limitation on the effective dose provides sufficient protection for the skin against stochastic effects. An additional limit is needed for localised exposures to prevent deterministic effects.


If nationally not available, the local Radiation ProtectionCommittee, should establish appropriate dose constraints, such as:

• Co-workers to the patient, and other members of the general

public: 0.3 mSv/procedure

DOSE CONSTRAINTSDOSE CONSTRAINTS



Module 12.2. Design considerationsModule 12.2. Design considerationsWorking proceduresWorking procedures


RADIOACTIVE CONTAMINATIONRADIOACTIVE CONTAMINATION

BSS III.7. BSS III.7. Registrants and licensees shall ensure that: Registrants and licensees shall ensure that:

(a) (a) for sources for which they are responsible, measures for sources for which they are responsible, measures that that are optimized in accordance with the requirements of the are optimized in accordance with the requirements of the Standards be taken as appropriate for restricting public Standards be taken as appropriate for restricting public exposure to contamination in areas accessible to the exposure to contamination in areas accessible to the public; and public; and

(b) (b) specific containment provisions be established for the specific containment provisions be established for the construction and operation of a source that could cause construction and operation of a source that could cause spread of contamination in areas accessible to the public. spread of contamination in areas accessible to the public.


Reduce the risk of Reduce the risk of uncontrolled contaminationuncontrolled contamination

Classification of areasClassification of areas Well trained staffWell trained staff Documented safe procedures in the Documented safe procedures in the

handling of radiopharmaceuticals (receipt, handling of radiopharmaceuticals (receipt, preparation, administration, waste preparation, administration, waste disposal)disposal)

Workplace monitoringWorkplace monitoring


Layout of a Layout of a nuclear medicine departmentnuclear medicine department

From high to low activity


CLASSIFICATION OF AREASCLASSIFICATION OF AREAS

•Controlled area•Supervised area


CONTROL OF VISITORSCONTROL OF VISITORS

BSS III.5. BSS III.5. Registrants and licensees, in co-operation with Registrants and licensees, in co-operation with employers when appropriate, shall: employers when appropriate, shall:

(a) (a) ensure that visitors be accompanied in any controlled ensure that visitors be accompanied in any controlled area area by a person knowledgeable about the protection and safety by a person knowledgeable about the protection and safety measures for that area; measures for that area;

(b) (b) provide adequate information and instruction to visitors provide adequate information and instruction to visitors before they enter a controlled area so as to ensure before they enter a controlled area so as to ensure appropriate protection of the visitors and of other appropriate protection of the visitors and of other individuals who could be affected by their actions; and individuals who could be affected by their actions; and

(c) (c) ensure that adequate control over entry of visitors to a ensure that adequate control over entry of visitors to a supervised area be maintained and that appropriate signs supervised area be maintained and that appropriate signs be posted in such areas. be posted in such areas.


Patient areasPatient areas• Separation of radioactive patients and other patients waiting is an example of good practice, especially in a busy department.

• Separate toilet room for the exclusive use of injected patients should always be considered. This patient washroom should not be used by general public or hospital staff as it is likely that the floor, toilet seat and sink faucet handles will be contaminated frequently.


STRUCTURAL SHIELDINGSTRUCTURAL SHIELDING

Patient with I-131

D mSv/h 0.3 mSv/procedure

Distance d

General public

The absorbed dose is determined by factors such as:• source strength;• length of exposure;• distance from the source;• transmission through the protective barrier.


• locked to prevent unauthorized use and theft• warning sign• shielded to <2 uSv/h at 1m (permanently occupied areas) alternatively <20 uSv/h at 1 m (temporarily occupied areas)• inventory record

• locked to prevent unauthorized use and theft• warning sign• shielded to <2 uSv/h at 1m (permanently occupied areas) alternatively <20 uSv/h at 1 m (temporarily occupied areas)• inventory record

STORAGE OF SOURCESSTORAGE OF SOURCES


RADIOACTIVE WASTERADIOACTIVE WASTE

BSS III.8. BSS III.8. Registrants and licensees shall: Registrants and licensees shall:

(a) ensure that the activity and volume of any radioactive waste (a) ensure that the activity and volume of any radioactive waste that results from the sources for which they are responsible be that results from the sources for which they are responsible be kept to the minimum practicable, and that the waste be kept to the minimum practicable, and that the waste be managed, i.e. collected, handled, treated, conditioned, managed, i.e. collected, handled, treated, conditioned, transported, stored and disposed of, in accordance with the transported, stored and disposed of, in accordance with the requirements of the Standards and any other applicable requirements of the Standards and any other applicable standard [26]; and standard [26]; and

(b) segregate, and treat separately if appropriate, different types of (b) segregate, and treat separately if appropriate, different types of radioactive waste where warranted by differences in factors radioactive waste where warranted by differences in factors such as radionuclide content, half-life, concentration, volume such as radionuclide content, half-life, concentration, volume and physical and chemical properties, taking into account the and physical and chemical properties, taking into account the available options for waste disposal. available options for waste disposal.


Discharge of radioactive substancesDischarge of radioactive substances

BSS III.9. BSS III.9. Registrants and licensees shall ensure that Registrants and licensees shall ensure that radioactive substances from authorized practices and sources radioactive substances from authorized practices and sources not be discharged to the environment unless: not be discharged to the environment unless:

(a) (a) the discharge is within the discharge limits authorized the discharge is within the discharge limits authorized by by the Regulatory Authority; the Regulatory Authority;

(b) (b) the discharges are controlled; the discharges are controlled; (c) (c) the public exposures committed by the discharges are the public exposures committed by the discharges are

limited as specified in Schedule II; and limited as specified in Schedule II; and (d) (d) the control of the discharges is optimized in accordance the control of the discharges is optimized in accordance

with the Principal Requirements of the Standards. with the Principal Requirements of the Standards.



Module 12.3. Module 12.3. The patientThe patient


The radioactive patientThe radioactive patientUncontrolled radioactive source Uncontrolled radioactive source that causes external exposure and that causes external exposure and contamination of the general contamination of the general public?public?

YES!(after leaving the hospital)


The Radioactive PatientThe Radioactive Patient

1000 MBqI-131

0 0.5 1 2 m

0.5 0.1 0.06 0.03 mSv/h

Contamination External

saliva perspiration breath urine


The radioactive patientThe radioactive patient

Keep the patient in the hospital

Release the patient without any restrictions

Release the patient with restrictions

Exposure of general public


The dose rate at 1 m from the patient should be down to an acceptable level established by the RPC.

Hospitalize:• >1100 MBq I-131Release with restrictions:• Treatment of thyrotoxicosis• Pain palliation (Sr-89, Sm-153)• Lactating women (specified

procedures)Release without restrictions:• Diagnostic procedures

Patient surveyPatient survey


• Use only a WC and flush 2-3 times. Keep the toilet and the floor

clean.• Wash Your hands frequently and take a shower every day.• Avoid close contact to members of the family, children and pregnant

women etc according to the time table attached• Avoid solid waste

INSTRUCTIONS TO OUT-PATIENTS(Example to minimize exposure of the general public)

Off work: 6d

Avoid close contact withchildren and pregnant women: 20 d

Public travel: 1h/day (1st week)



Module 12.4. Special problemsModule 12.4. Special problems


In the event of death of a patient who has recently received a therapeutic dose of a radionuclide care has to be taken toensure that personnel receive as low dose as possible at all stages prior to the burial or cremation.

Radionuclide Burial Cremation I-131 400 400 Y-90 colloid 2000 70 Au-198 colloid 400 100 P-32 2000 30 Sr-89 2000 200

DEATH OF PATIENTDEATH OF PATIENT

Activity (MBq)

(UK)


Precautions that should be given are depending on the residual activityand the expert advice provided by the RPO and may involve the following:

• preparation for burial or cremation should be controlled by a competent person,• relatives should be prevented from coming into close contact with the body,• people should not be allowed to linger in the presence of the coffin,• all personnel involved in handling the corpse should be instructed by the RPO and monitored if appropriate,• all objects, clothes, documents etc that might have been in contact with the deceased must be tested for contamination,• it may be expedient to wrap the cadaver in waterproof material immediately after death to prevent spread of contaminated body fluids,• embalming of cadavers should, if possible, be avoided,• autopsy of a highly radioactive cadavers should be restricted to the absolute minimum

DEATH OF PATIENT



Module 12.5. TransportationModule 12.5. Transportation


TRANSPORT CONTAINERTRANSPORT CONTAINER

Cartoon

Liner

Sealed can

Liner

Lead container

Source


Transport ContainerTransport Container


Transport Index (TI)Transport Index (TI)

1.0 m

TI = max dose-rate @ 1.0m (Sv/h)

10


White-I LabelWhite-I Label

< 5.0 Sv/h @ surface

< 0.05 Sv/h @ 1.0 m

TI = 0


Yellow-II LabelYellow-II Label

< 500 Sv/h, > 5 Sv/h

@ surface

< 10 Sv/h @ 1.0 m

0 < TI < 1.0


Yellow-III LabelYellow-III Label

> 500 Sv/h,< 2000Sv/h

@ surface

> 10Sv/h, < 100Sv/h

@ 1.0m

1.0 < TI < 10


Vehicle PlacardsVehicle Placards

3 placards on vehicle


Consignor’s ResponsibilitiesConsignor’s Responsibilities

all labelling and placardingall labelling and placarding provision of transport documentsprovision of transport documents provision of local rules and any other relevant provision of local rules and any other relevant

informationinformation


Internal transportInternal transportIf the administration of radiopharmaceutical to the patient takes place far from the dispensing room, use a transport container withabsorbent pads.

Make sure that a warning sign is on the container togetherwith patient name, activity and date.

Travel by the most direct route avoiding more heavilyoccupied areas


Questions?


DISCUSSIONDISCUSSION

You get a phone-call from a colleague in anotherhospital about 0.5 h away. He is in an urgent need of Tc99m-MAA for a lung scan. Can you help him?



You get a phone call from a relative to a patient whoyesterday got 4 GBq Sm-153. The patient died at hometoday. What to do?



A patient has received 300 MBq I-131 in a treatmentof thyrotoxicosis. She is working in a school preparingfood for the children. She was told to stay off work for2 weeks. You get a message that she actually wentback to work the day after the treatment, which was10 days ago. What to do?


Where to Get More Where to Get More InformationInformation Other sessions

Part 4. Security of sources, Design of facilities Part 5. Occupational protection Part 6. Medical exposure Part 8. Optimization of medical exposure. Therapeutic

procedures Part 10. Radioactive waste

Further readingsFurther readings IAEA Basic Safety Standards IAEA Model regulations on radiation safety in nuclear medicine

(in preparation) WHO. Manual on Radiation Protection in Hospitals and General

Practices. Volume 4: Nuclear Medicine (in preparation)

Documents

Part 12 IAEA Training Material on Radiation Protection in Nuclear Medicine Protection of the General Public