AP Training Logo Introduction Radiation is useful in medicine because of its ability to penetrate tissue, allowing imaging and non-surgical treatment of internal structures. Radioactive materials (isotopes or Radio-nuclides ) and radiation equipments are commonly used in the diagnosis and therapy (treatment) of patients. However, radiation may produce harmful biological effects. Use of radiation has to be justified and minimized for patients, co-workers and members of public. The responsible use of radiation must benefit the patient and the investigation of disease and treatment must outweigh risk of possible harmful effects. Principle of ionizing radiation safety In hospital environment (Ver.1.0)
The purpose of this module is to inform members of the clinical staff about the impact and safe usage of radiation apparatus and radioactive materials for the health and well-being of their patients, the members of the public and themselves.
Clinical staffs, nurses, doctors, radiologist, radiographers, medical physicist , biomedical engineers and hospital management team members.
At the end of this course, student will understand the :-
-characteristics of ionizing radiation,
-nature of radiation hazards,
-basic radiation protection and safety,
-concept of ALARA (As Low As Reasonably Achievable) principle.
-basic principle which consist of three factors “Time, Distance and Shielding” in order to minimize the radiation exposure in general.
-unique features of radiation protection and safety for each equipment models.
Principle of ionizing radiation safety In hospital environment (Ver.1.0)
Contents 1. Radiation and its effects on human 1.a What is ionizing Radiation 1.b Types of radiation 1.c How the X Ray Tube works 1.d Commonly used radioactive materials in the hospital environment 1.e How does radiation interact with human tissue 1.f Radiation accidents 1.g Young and rapid growing cells are more sensitive than mature cells 1.h Comparison of Administrative, Regulatory and Biological Effect Doses (Example) 2. Basic radiation safety principles, practices and monitoring devices 2.a ALARA Principle 2.b Basic radiation safety principles and practices 2.c Personnel monitoring devices 2.d Area monitoring devices 3. Mode of ionizing radiation exposures in hospital environment 4. Use of r adiation in hospital departments by equipment modalities 4.a X-Ray Radiograph 4.b Fluoroscopy 4.c Angiography 4.d Mammography 4.e Computed Tomography 4.f Dose comparison 4.g Common Shielding 4.h Nuclear Medicine 4.i Brachytherapy 4.j Radiotherapy 5. Emergency situation 6. Laws, Regulations and Standards and Radiation Safety Organization 7. Questions Principle of ionizing radiation safety In hospital environment (Ver.1.0)
1.f.iv Radiation accidents due to angiogram procedure
Biological effects depend on radiation dose
Acute vs. Chronic exposures
Acute - High dose received in a short period of time.
Chronic – Low dose received over a long period of time.
Patient suffers radiation over dose injury after an angiogram few weeks later. Fig-1, Fig-2, Fig-3 and Fig-4. (Source FDA)
1.f-v Radiation accidents due to radioactive material
High Typically young and rapid growing cells are more sensitive to the radiation than mature cells . 1.g Young and rapid growing cells are more sensitive than mature cells Hair follicles are fast growing cell therefore during radiation treatment you will notice hair loss. Sensitivity Low Muscle, Joints, Central nerves, Fat Skin, Inner-layer of intestines, Eyes Bone marrow, Lymph system, Reproductive organs
1.h Comparison of Administrative, Regulatory and Biological Effect Doses (Example) 100% of People Die, CNS Syndrome Permanent Infertility Radiation Worker Whole Body Regulatory Limit (20 mSv/yr) Eye Regulatory Limit (150 mSv/yr) 50% of People Die (450 – 500 rad) Nausea & Vomiting (10% of People) Whole Body Exposure Partial Body Exposure Extremities Regulatory Limit (500 mSv/yr) Rad or Rem General Public Whole Body Regulatory Limit (1 mSv/yr) No Clinical Symptoms Seen Below 100mSv Cataract Formation Loss of Hair Skin Reddening Decreased White Blood Cell Count Ulcers on the Skin Molecular Death (> 100,000 rad) Gastrointestinal Syndrome (1 rem = 10 mSv)
Ionizing radiation should be used only if other non-ionizing equipment can not perform the equivalent performance results.
Doses A s L ow A s R easonably A chievable
ALARA (As Low As Reasonably Achievable) means that every reasonable effort shall be made to maintain radiation exposures as far below the dose limits as practical, taking into account the state of the technology, the economics of the improvements in relation to the benefits, and other socioeconomic considerations.
Absolute legal limits for staff and public
Reference levels as guidance for patients .
Adult Occupational Limit
5000 mrem (2.0 rem) or 20 mSv / year
Member of the Public
100 mrem (0.1 rem) or 1 mSv / year
2. Basic radiation safety principles, practices and monitoring devices Put picture of scale
2.a ALARA Principle Flash file 06_ALARA LINK TO Alara SLIDE.
Good practice: Wear the badge between your waist and collar and make sure that the badge worn is the one issued in your name for the current monitoring period. Do not share badges with other workers.
(Survey Meters) These Survey Meters are used to detect leakage radiation of x-ray rooms. This type of survey meters are equipped with ionization chamber type detector. It is not suitable for Alpha, Beta and Neutron particles. But could be usable for high range of Gamma radiation. These Survey Meters are used to detect contamination radiation at Nuclear Medicine Department. For different particles such as Alpha, Beta, Gamma, Neutron, different detector has to be used. 2.d Area monitoring devices All survey meters are required to sent to authorized laboratory such as “Nuclear Malaysia Agency for annual calibration and certification.
Irradiation e.g. X-ray equipments External Contamination e.g. Tc-99M Nuclear Medicine Internal Contamination e.g. Neutron radiation In Hi-energy ranges 3. Mode of ionizing radiation exposures in hospital environment
4. Use of radiation in hospital departments by equipment modalities
Radiology Imaging Department
Nuclear Medicine Diagnostics and Therapy Department
Radiation Oncology Department (Radiotherapy)
where ionizing radiation and radio active materials are being used to diagnose and treat patients
4.a X-Ray Radiograph (Radiation Safety in Radiology Department ) Only patient remain inside the room and operator and all other personnel stay out side the room. X-ray room is equipped with a lead-glass window to monitor the patient. Radiation warning light is installed above all entry doors to indicate risk.
07_General X Ray System Imaging 4.a.i X-Ray Radiograph (Radiation Safety in Radiology Department )
4.b Fluoroscopy Systems (Radiation Safety in Radiology Department) Patient and operator, normally radiographer and may be radiologist remain inside the room during examination procedure. The other personnel stay out side the room. Fluoroscopy / Angiography room is equipped with a lead-glass window to monitor the patient. Radiation warning light is installed above all entry doors to indicate risk. A typical dose profile for a fluoroscopy system Comparison between Over-Table Tube and Under-table Tube positions on dose profiles A typical Fluoroscopy system, provide radiation protection lead leaves
4.c.i Angiography Systems (Radiation Safety in Radiology Department) CARDIOVIEW.swf TOPSPEED.swf
File_08 Radiation risk to operator (Angio)_1 File_08 Radiation risk to operator (Angio)_2 4.c.ii Angiography Systems (Radiation Safety in Radiology Department)
Guidelines for Allied Health Personnel Working with Radiographic/Fluoroscopic Procedures
A personnel monitoring dosimeter (Film badge or TLD) should always be worn when working with
radiographic/fluoroscopic equipment or in radiographic/fluoroscopic procedures.
The dosimeters worn should be those issued for the current time period and should be worn at the collar. Put the picture, see at next page …..Create the Next Button and paragraphs will move in.
Remain in room during radiographic/fluoroscopic procedures only if necessary. Less time spent
around a radiation source means a lower radiation exposure to the individual.
Remember: The main source of exposure is radiation scattered from the patient.
If you must remain in the room during these procedures, you must wear a lead apron of at least 0.25
mm lead equivalence. Note: A lead apron of 0.25 mm lead equivalence will reduce scattered
X- rays by 95%.
Since radiation decreases rapidly with distance, the further one is from the patient during the actual
X-ray examination, the smaller your exposure. Maintain the maximum distance possible from the
patient during radiography and fluoroscopy.
If equipment has radiation dose reduction techniques or procedures, these features should be utilized in order to minimize the amount of radiation such as Pulsed Fluoroscopy, Additional Filtration, digital image storage for Road Mapping procedures, Gap Filling of images in between exposures, simulation of x-ray beam collimation, monitor the dose monitoring devices such as Dose Area Product device (DAP), observe the radiation on-time warning system lamp or audio.
Follow regulatory requirements in yearly testing and certification and in maintaining the equipment
in good working order.
4.c.iii Angiography Systems (Radiation Safety in Radiology Department)
4.d Radiation Safety in Radiology Department Mammography Systems Mammography systems come with built-in lead-glass panel that allows the operator stands safely inside the examination room. Comparison between digital & analog images A modern Mammography System and patient. Typical position of x-ray tube and patient with compression.
4.e Radiation Safety in Radiology Department Computed Tomography Systems Radiation dose profile for Computed Tomography system A typical Computed Tomography System A typical Computed Tomography Suite Only patient is to remain inside the room while the operator and all other personnel stays outside the examination room. CT room is equipped with a lead-glass window to monitor the patient during the exposure. Radiation warning light is installed above all entry doors to indicate risk.
Approximate Dose being used in Medical Diagnostics Procedures Medical Diagnostics, mSv A- Chest x-ray (1 film) 0.1 B- Dental oral exam 1.6 C- Mammogram 2.5 D- Lumbosacral spine 3.2 E- PET 3.7 F- Bone (Tc-99m) 4.4 G- Cardiac (Tc-99m) 10 H- Cranial CT (MSAD) 50 (multiple scan average dose) I- Barium contrast G-I 85 fluoroscopy (2 min scan) J- Spiral CT- full body 30-100 Absorbed dose: 1 Gray = 100 rad Dose equivalent: 1 Sievert = 100 rem 1 mSv = 100 mrem (1 Sv = 1 Gy for x- and gamma-rays)
Adult Occupational Limit
5000 mrem (5.0 rem) or 50 mSv / year
Member of the Public
100 mrem (0.1 rem) or 1 mSv / year
4.f.i Radiation Safety in hospital environment Modalities and Departments involved
Approximate Dose for operator in Medical Diagnostics Procedures Flash File 07_Comaprison 4. f.ii Radiation Safety in hospital environment Modalities and Departments involved
Personnel Protective Equipment (Shielding) used in Radiology Department. 4.g.i Common shielding devices (Radiology Department) Variety of lead aprons found in a typical radiology department. Some are supposed to be worn and some are designed to placed in front of operator.
Controlled and clean areas (Shielded Rooms) CT Room Entrance Example illuminated warning sign sliding shielded doors radiation warning sign 4.g.ii Radiation Safety in Radiology Department required shielded rooms A typical radiation shielded room for diagnostics equipments. Requirements are: Minimum thickness of wall > 2 mm lead eq. Radiation warning light and symbol sticker out side the room Size of the room is defined by MOH.
4.h.i Radiation Safety in Nuclear Medicine Department The gamma rays have properties like x-rays. They emit out of the patient's body, and therefore present a potential external hazard to bystanders. To reduce this hazard, some patients may be placed in special lead-lined rooms for a few days. You can work safely with these patients by using a few simple techniques: (1) Put on shoe covers and protective gloves before entering the patient's room. (2) Work quickly, but effectively and courteously. (3) Maintain the greatest distance possible from the patient consistent with effective care. Radiation exposure drops off drastically with increasing distance. (4) Observe Universal Precautions while handling blood and other body fluids, especially urine. (5) Leave all trash, linens and food trays in the room. Upon leaving the room, remove gloves and shoe covers and place them in the trash box inside the room. (6) After leaving the room, wash your hands. (7) In the event of a medical emergency involving the patient, the patient's well-being is the primary consideration. All initial measures necessary to sustain the patient should be undertaken, regardless of radiation considerations. It may be possible to further reduce the external hazard by using portable shields. In general, lead aprons are minimally effective and their routine use during ordinary caregiving is not recommended. However, during prolonged procedures at close proximity to the patient (for example, a difficult blood draw), they can reduce exposure by about 15%.
Shielding being used in Nuclear Medicine Department. 4.h.ii Radiation Safety in Nuclear Medicine Department
Radioactive materials are being used in Nuclear Medicine Imaging Department (Molecular Imaging) (i) Gamma Camera which involve radionuclide such as Technetium 99m, I-131. (ii) Positron emission tomography (PET) 18-FDG Nuclear Medicine Diagnostics Nuclear Medicine Diagnostic Patients Patients may undergo imaging procedures in Nuclear Medicine while hospitalized. These procedures include bone scans, gallium scans, PET scans and so forth. They are performed with very small ("tracer") amounts of radioactive materials. The radiation levels from these patients are negligible, and present almost no hazard. Other than "Universal Blood and Body Fluid Precautions", there are no special radiation safety considerations for interacting with these patients. 4.h.iii Radiation Safety in Nuclear Medicine Department Diagnostics
4.h.iv Radiation Safety in Nuclear Medicine Department Treatment Nuclear Medicine Therapy Patients Most of these patients are treated with radioactive iodine-131 (I-131). Iodine-131 has a half-life of 8 days and emits both beta particles and gamma rays . The beta particles are responsible for killing the tumor cells. They have such a short "range" in tissue that they do not leave the patient's body, and so present no external hazard. However, gamma rays emitted from I-131 could strong enough to give exposures to environment. These patients are being confined in a radiation shielded rooms for 2 to 3 days. Moreover , I-131 is excreted in the patient's urine, stools, saliva and perspiration, small amounts of radioactivity may be present on surfaces in the patient's room. This "contamination" can be ingested by "surface-to-hand-to-mouth" contact. A dedicated toilet is located inside these patient’s rooms and a special system collects and stores all waste in “Decay Tanks” for months before discharge to the main sewer.
Iodine-131 Therapy for Cancer of the Thyroid I-131 is used to treat patients with thyroid carcinoma or hyperthyroidism. I-131 is generally administered orally in a liquid, capsule, or caplet form. Any patient receiving major therapies may be admitted to the hospital as determined by patient-specific dose calculations. Radiation exposure and contamination are both concerns when working with I-131 patients. Since patient will become radioactive after having been given the treatment and will emit radiation patient will be required to remain within “The radionuclide treatment suite” until they are advised that it is safe to leave. This consists of a room, shower / bath and toilet. Patient will excrete a considerable amount of radioactive iodine in urine, faeces, sweat, saliva and nasal mucous and it is therefore very important that these substances are not allowed to 'contaminate‘ other people, or areas outside the suite. Patient may ONLY use the toilet, shower and washing facilities WITHIN the radionuclide suite. 4.h.v Radiation Safety in Nuclear Medicine Department Treatment
Guidelines for Nursing Personnel Working with I-131 Therapy Patients
The following guidelines should be observed when working with I-131 patients:
Always wear your personnel monitoring badge (dosimeter) when attending the patient. Wear the badge between your waist and collar and make sure that the badge worn is the one issued in your name for the current monitoring period. Do not share badges with other workers. When you are not working, store your badge in a controlled area away from all radiation sources.
Provide all necessary care, but:
-try to minimize time spent with patient
-work no closer to patient than necessary
-wear disposable gloves, gowns, and booties when attending patient
Carefully note instructions posted with the “Caution Radiation” sign and any radiation safety instructions written in the patient’s chart.
As primary contact for matters of the patient’s care, be prepared to answer questions from other nurses, physicians, technical staff members, and visitors.
Housekeeping and Dietary staff are not permitted in I-131 patient rooms.
I-131 patients are to be provided with isolation food trays.
Notify Radiation Protection Officer (RPO) and Nuclear Medicine Department Head (see posted emergency numbers) if there is a spill of patient urine, the patient vomits or if there is a medical emergency (including patient death).
4.h.vi Radiation Safety in Nuclear Medicine Department Treatment
4.i.i Radiation Safety in Brachytherapy Department A typical Brachytherapy treatment shielded room (as thick as 60 cm concrete wall A typical Brachytherapy system Image of source positioning
4.i.ii Radiation Safety in Radiotherapy Department (Brachytherapy) In brachytherapy , small, sealed sources of radiation (typically Cs-137 or Ir-192), are positioned near the patient’s cancer site using special, surgically-implanted catheters. While these catheters are implanted in the operating room, the radiation sources themselves are inserted into these catheters in the patient’s room. Implant therapy is effective in some cases of uterine, prostate and lung cancer than external radiation therapy. In this case, a sealed source radioactive material, usually a gamma emitter such as cesium (CS-137) or iridium (Ir-192, is placed in a body cavity close to the tumor and left in place for a prescribed period of time say about 20 minutes. During the time the implant is in place, staff entering the room are exposed to gamma rays and must take precautions. Once the treatment is completed and the implant is removed, the patient is no longer radioactive and presents no hazard. Radiation exposure is the primary concern when working with brachytherapy patients. Contamination is not of concern as the radiation sources are “sealed.”
Put on protective gloves before entering the patient's room. Although breakage of a sealed
source is an unlikely occurrence, ingestion of radioactivity is easily prevented by wearing gloves.
(2) Work quickly, but effectively and courteously. Minimize your time in the room.
(3) Maintain the greatest distance possible from the patient consistent with effective care. Radiation
exposure drops off drastically with increasing distance.
(4) Leave all trash, linens and food trays in the room. Upon leaving the room, remove gloves and
place them in the trash receptacles inside the room. Radiation Safety surveys all materials
before they leave the room.
(5) After leaving the room, wash your hands.
In the event a source becomes dislodged, notify the Radiation Oncology resident on call
immediately . Do not permit others to enter the room until the source is secured. Do not attempt to
handle a dislodged implant or applicator, unless you are specially trained to do so.
4.i.iii Radiation Safety in Radiotherapy Department (Brachytherapy) Guidelines for Nursing Personnel Working with Brachytherapy (Implant) Patients
4.j.i Radiation Safety in Radiotherapy (Treatment) Department (Linac) Radiation Therapy (or radiotherapy) is the medical use of ionizing radiation as part of cancer treatment. DNA in cancer cells which enables the cancerous cells to reproduce is damaged by radiation therapy. When the damaged cells die, the body eliminates them. Normal cells which may have been effected by radiation can repair themselves. Treatment can be delivered external to the body, (i.e. external beam radiation therapy) . A typical Linear Accelerator (Linac) Suite
4.j.ii Radiation Safety in Radiotherapy (Treatment) Department (Linac) A typical shielded room for Linear Accelerator (Linac). The shielded wall could be as thick as 1 to 2 meters of concrete, depends on energy employed
5. Emergency situation When there is an emergency accident involved with radioactive material, the effected area should be sealed to avoid unauthorized personnel to enter the site and appropriate source container should get ready to contain the radioactive material.
Regulatory requirements (Radiation Warning Sign Stickers) which are mandatory to placed outside the radiation room and during transport This sticker is used for X-Ray radiation This sticker is used for radioactive materials This sticker is used for transport of radioactive materials (Container) 6.a Laws, Regulations and Standards and Radiation Safety Organization
40 (1) Any person who contravenes any of the provisions of this Act commits an offence under
(2) Any person who commits an offence under this Act is, on conviction,
where no penalty is expressly provided there for, liable to imprisonment for
a term not exceeding ten years or fine not exceeding one hundred thousand
Ringgit or both.
(3) Where an offence under this Act is committed by a body corporate, every person who at
the time of the commissioning of the offence was a director or officer of that body
corporate commits that offence.
6.c Laws, Regulations and Standards and Radiation Safety Organization
Licensee (SMSB) Person In-Charge Towards License (OBTL) Name………….. Radiation Protection Officer (RPO) Name …………. Individual Radiation Workers 6.d Laws, Regulations and Standards and Radiation Safety Organization
7.i Questions Q.1 It is called ionizing radiation, because, these radiation carry enough energy to knock out _______ from an atom and atom become ionized due to electrically unstable state. Q.2 What is the type of ionizing radiation commonly found in hospital Imaging Department? Q.3 What type of radiation produced by Fluoroscopy system? Q. 4 What type of radiation produced by Brachytherapy system? Q.5 Basic concept of radiation protection is based on ______, Optimization and Limit of Dose. Q.6 ALARA stands for: Q.7 The ALARA concept is based on the assumption: a. nucleus d. proton e. water b. electron c. DNA a. Alpha b. Beta c. Gamma d. X-ray e. Neutron a. Gamma b. Neutron c. X-Ray d. Alpha e. Positron a. Gamma b. Neutron c. X-ray d. Electron e. Positron b. Justification a Just In Time c. Shielding d. Time a. as long as regulation allows b. as low as reasonably achievable c. as low as rationally attainable a. that only a large radiation dose can be harmful b. that any radiation dose can have some adverse effect c. That a little radiation dose can be beneficial e. Distance
7.iii Questions Q.8 What is the Annual Dose Limit for radiation workers? a.100 mSv b. 50mSv c. 20mSv d. 1mSv e. 0.1 mSv Q.9 What is the Annual Dose Limit for public? (Please choose one.) a.100 mSv b. 50mSv c. 20mSv d. 1mSv e. 0.1 mSv Q.10 The three basic principles used in protecting oneself from radiation exposure are: a. time, distance, shielding b. ventilation, rules and regulations, procedures c. containment, protective clothing, surveys d. Justification, Optimization, Limit of Dose e. avoid radiation, avoid long working hours, avoid touching the radioactive materials Q. 11 A radiation worker is required to be monitored if: a. he/she is likely to receive in excess of 10% of the dose limits b. he/she wants to be c. if the annual radiation dose is likely to be greater than 10 milli sievert d. if any radiation is present in the workplace e. xxxx
7.iv Questions Q. 12 A 0.25 mm lead equivalent apron will reduce scattered X-rays by: (Please choose one.) a. 10% b. 20% c. 50% d. 70% e. 90% Q. 13 Which statement about brachytherapy is FALSE: a. you should try to work behind mobile shields whenever possible b. other hospital staff members are allowed in patient rooms if stay times and posted instructions are observed c. pregnant visitors and minors ARE allowed in radiation isolation rooms d. the room and patient ARE NOT to be released until cleared by Radiation Safety e. Q. 14 If a brachytherapy source becomes dislodged from the patient, you should: a. not touch the source b. remove all unnecessary personnel and call Radiation Safety and Radiation Oncology c. try to get the source to the corner of the room with a broomstick, etc. d. do all of the above e. Q. 15 Radiation is useful in medical diagnosis because: a. of its ability to cause biological damage b. lead walls can absorb it c. of its ability to penetrate tissue d. it is easy to get a radiation-use license e.