RADIATION PROTECTION OF WORKERS Nuclear Medicine€¦ · Radiation doses to staff must be kept: As...
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If contamination is present Remember DOSE AND EFFECTS þ þ PROCEDURES EXTERNAL EXPOSURE INTERNAL EXPOSURE Nuclear Medicine External exposures to staff can occur: From any exposure to a significant quantity of unshielded radioactive material. When working with vials, syringes or transport boxes containing radioactive material. During contact with a patient after radio- pharmaceutical administration, e.g. after radioiodine therapy. þ þ þ Time To reduce radiation doses, the time spent in radiation areas must be kept as short as possible. The longer the time spent in an area, the higher the dose received. In an area where the dose rate is 100 Sv/h, the dose received will be: μ Distance 1 cm of plastic will totally shield all beta radiation. Lead and concrete can be used to shield against gamma and X radiations. Shielding material must be appropriate for the type of radiation. For example: 0 minutes 15 minutes 30 minutes 1 hour 2 hours 0 μSv 25 μSv 50 μSv 100 μSv 100 μSv/h 200 μSv Shielding plastic lead concrete 1 m 2 m 25 μSv/h If the dose rate at 1 m from a source is 100 /h. μ μ Sv/h, the dose rate at 2 m will be 25 Sv þ þ Do not touch anything. A contaminated person should contact the Radiation Protection Officer. þ Keep away from other contaminated areas, unless an injured person needs help. þ þ þ þ þ þ Always w the assigned dosimeters according to the instructions. A female worker should, on becoming aware that she is pregnant, notify the employer in order that her working conditions may be modified if necessary. Avoid contamination. Use a contamination survey meter. Clean up spills as soon as practicable, following instructions or local rules. Take extra precautions when looking after patients treated with high activity radiopharmaceuticals. ear þ þ þ þ þ þ þ Whenever hospitalization is required, the patient must stay in a designated, shielded and isolated room. Waste from the toilet and sink will be radioactive and must be carefully managed. The area around the patient's toilet should be covered in absorbent paper to contain any contamination. Staff must have extra training. Staff must wear protective clothing, limit their time in the room, and whenever possible, keep a shield between them and the patient. Staff must wear personal dosimeters. After the patient leaves, the room must be thoroughly cleaned and monitored. The room must be confirmed as being safe for use by the Radiation Protection Officer before being used again. Clothes and materials handled by the patient must be handled separately and decontaminated. Always monitor: The nuclear medicine laboratory, especially at the end of any period of work. The hands and shoes of staff whenever leaving the laboratory. Equipment that has been used and cleaned. The radioactive material store. þ þ þ þ þ þ þ þ þ Cover cuts and wounds. Do not eat, drink, smoke or apply cosmetics. Clean up spills, even minor splashes, as soon as practicable. Not touch things unnecessarily. Wash your hands immediately. þ þ þ Wear protective clothing. Wear latex gloves. Wear overshoes. CONTAMINATION There may be contamination: Where splashes or spills have occurred. On laboratory surfaces. Through the sweat, saliva and excreta of patients. þ þ þ Others must: Radioactive material can enter the body by inhalation, ingestion and by absorption through intact or damaged areas of the skin. The presence of radioactive contamination presents an internal exposure risk to staff for each of these exposure routes. Where there is contamination, you should: SHIELDING Use syringe shields for the preparation and administration of radiopharmaceuticals. Leaded shields can help to reduce dose rates. Waste must be disposed of in a strictly controlled and prescribed way. Keep checking for contamination! Contaminated areas must be cleaned up carefully and surveyed again. RADIOIODINE THERAPY The activities in radioiodine therapy are so large that the external exposure from the patient becomes signficant. MONITORING Radiation doses to staff must be kept: As Low As Reasonably Achievable: ALARA Tc-99m 10 GBq 560 mSv/h 1 mSv/h 2 mm lead Use tongs to handle sources. Nuclear medicine is a special field of medicine in which radioactive material is used to diagnose (detect) and treat medical disorders. One can receive a radiation dose exposure to nuclear medicine sources from outside the body (external exposure) or if the radioactive material enters the body (internal exposure). from Units of dose Dose rate Health effects of radiation exposure The unit of absorbed dose is the gray (Gy). The unit used to quantify the dose in radiation protection is the sievert (Sv). One millisievert (mSv) is 1/1000 of a sievert. One microsievert ( Sv) is 1/1000 of a millisievert. Dose rate is the dose received in a given time. The unit used is microsieverts per hour ( Sv/h). If a person spends two hours in an area where the dose rate is 10 μSv/h, then they will receive a dose of 20 μSv. Annual doses from natural background radiation vary on average between 1 mSv and 5 mSv worldwide. μ The typical dose from a chest X ray is 20 μSv. μ In nuclear medicine, there is hardly any chance of deterministic effects rising among staff unless the hand or skin is heavily contaminated. Use of the ALARA principle and the regular monitoring of personal dose can minimize the risk of stochastic effects arising. AS LOW AS REASONABLYACHIEVABLE (ALARA) RADIATION PROTECTION OF WORKERS Dosimeters Dosimeters do not provide protection from exposure to ionizing radiation. They are a means of assessing the dose the wearer has received : Finger dose monitoring may be appropriate for those dispensing or injecting radiopharmaceuticals. . WASTE External exposures can be controlled by consideration of time, distance and shielding.
Transcript of RADIATION PROTECTION OF WORKERS Nuclear Medicine€¦ · Radiation doses to staff must be kept: As...
If contamination is present
Remember
DOSE AND EFFECTS
þ
þ
PROCEDURES
EXTERNAL EXPOSURE
INTERNAL EXPOSURE
Nuclear Medicine
External exposures to staff can occur:
From any exposure to a significant quantity ofunshielded radioactive material.
When working with vials, syringes or transportboxes containing radioactive material.
During contact with a patient after radio-pharmaceutical administration, e.g. after radioiodinetherapy.
þ
þ
þ
Time To reduce radiation doses, the time spent in radiationareas must be kept as short as possible. The longer the timespent in an area, the higher the dose received.In an area where the dose rate is 100 Sv/h, the dosereceived will be:
µ
Distance
1 cm of plasticwill totally shield allbeta radiation.
Lead and concrete canbe used to shield againstgamma and X radiations.
Shielding material must be appropriate forthe type of radiation. For example:
0 minutes 15 minutes 30 minutes 1 hour 2 hours
0 µSv 25 µSv 50 µSv 100 µSv
100 µSv/h
200 µSv
Shielding
plastic lead concrete
1 m
2 m
25 µSv/h
If the dose rate at 1 m from a source is 100/h.
µ
µ
Sv/h,the dose rate at 2 m will be 25 Sv
þ
þ
Do not touch anything.
A contaminated person should contact theRadiation Protection Officer.
þ Keep away from other contaminated areas,unless an injured person needs help.
þ
þ
þ
þ
þ
þ
Always w the assigned dosimeters accordingto the instructions.
A female worker should, on becoming awarethat she is pregnant, notify the employer in orderthat her working conditions may be modified ifnecessary.
Avoid contamination.
Use a contamination survey meter.
Clean up spills as soon as practicable, followinginstructions or local rules.
Take extra precautions when looking afterpatients treated with high activityradiopharmaceuticals.
ear
þ
þ
þ
þ
þ
þ
þ
Whenever hospitalization is required, the patientmust stay in a designated, shielded and isolatedroom. Waste from the toilet and sink will beradioactive and must be carefully managed.
The area around the patient's toilet should becovered in absorbent paper to contain anycontamination.
Staff must have extra training.
Staff must wear protective clothing, limit their timein the room, and whenever possible, keep ashield between them and the patient.
Staff must wear personal dosimeters.
After the patient leaves, the room must bethoroughly cleaned and monitored. The roommust be confirmed as being safe for use by theRadiation Protection Officer before being usedagain.
Clothes and materials handled by the patientm u s t b e h a n d l e d s e p a r a t e l y a n ddecontaminated.
Always monitor:
The nuclear medicine laboratory, especially at the end of any periodof work.
The hands and shoes of staff whenever leaving the laboratory.
Equipment that has been used and cleaned.
The radioactive material store.
þ
þ
þ
þ
þ
þ
þ
þ
þ
Cover cuts and wounds.
Do not eat, drink, smoke or apply cosmetics.
Clean up spills, even minor splashes, as soon aspracticable.
Not touch things unnecessarily.
Wash your hands immediately.
þ
þ
þ
Wear protective clothing.
Wear latex gloves.
Wear overshoes.
CONTAMINATIONThere may be contamination:
Where splashes or spills have occurred.
On laboratory surfaces.
Through the sweat, saliva and excreta of patients.
þ
þ
þ
Others must:
Radioactive material can enter the body by inhalation,ingestion and by absorption through intact or damagedareas of the skin. The presence of radioactivecontamination presents an internal exposure risk to stafffor each of these exposure routes.
Where there is contamination, you should:
SHIELDING
Use syringe shields for the preparation and administrationof radiopharmaceuticals.
Leaded shields can help to reduce dose rates.
Waste must be disposed of in a strictly controlled andprescribed way.
Keep checking for contamination!
Contaminated areas must be cleaned up carefully and surveyed again.
RADIOIODINE THERAPY
The activities in radioiodine therapy are so large thatthe external exposure from the patient becomessignficant.
MONITORING
Radiation doses to staff must be kept:
As Low As Reasonably Achievable: ALARA
Tc-99m10 GBq 560 mSv/h
1 mSv/h2 mm lead
Use tongs to handle sources.
Nuclear medicine is a special field of medicine in whichradioactive material is used to diagnose (detect) andtreat medical disorders. One can receive a radiation dose
exposure to nuclear medicine sources from outside thebody (external exposure) or if the radioactive materialenters the body (internal exposure).
from
Units of dose
Dose rate
Health effects of radiation exposure
The unit of absorbed dose is the gray (Gy).
The unit used to quantify the dose in radiationprotection is the sievert (Sv).
One millisievert (mSv) is 1/1000 of a sievert.
One microsievert ( Sv) is 1/1000 of a millisievert.
Dose rate is the dose received in a given time.The unit used is microsieverts per hour ( Sv/h).
If a person spends two hours in an area where thedose rate is 10 µSv/h, then they will receive a dose of20 µSv.
Annual doses from natural background radiation varyon average between 1 mSv and 5 mSv worldwide.
µ
The typical dose from a chest X ray is 20 µSv.
µ
In nuclear medicine, there is hardly any chance ofdeterministic effects rising among staff unless the handor skin is heavily contaminated.
Use of the ALARA principle and the regular monitoring ofpersonal dose can minimize the risk of stochastic effectsarising.
AS LOWAS REASONABLYACHIEVABLE (ALARA)
RADIATION PROTECTION OF WORKERS
DosimetersDosimeters do not provide protection from exposure to ionizing radiation. They are a means of assessingthe dose the wearer has received
: Finger dose monitoring may be appropriate for those dispensing or injecting radiopharmaceuticals.
.
WASTE
External exposures can be controlled by considerationof time, distance and shielding.
