Chapter 10 Flashcards
An EfD limiting system has been incorporated into what title of Federal Regulations
Title 10, Part 20
Title 10, Part 20 is a document prepared and distributed by the:
US Office of the Federal Register
What is the basis of the EfD Limiting System
Concept of radiation exposure and of the assiocated risk of radiation-induced malignancy
What reports revised the EfD limiting system
NCRP Report 116
ICRP Report 60
What is in Title 10 of the Code of Federal Regulations besides dose limits
Rules and regulations of the NRC and fundamental radiation protection standards governing occupational radiation exposure
Reasons medical imaging professionals must be familiar with previous, exisiting, and new guidelines for radiation safety
Share the responsibility for patient safety
Subject to radiation exposure in the performance of their duties
How many organizations are responsible for evaluating the relationship between radiation EqD and induced biologic effects
4
What are the 4 radiation protection standards organizations?
International Commission on Radiological Protection (ICRP)
National Council on Radiation Protection and Measurements (NCRP)
United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR)
National Academy of Sciences/National Research Council Committee on the Biological Effects of Ionizing Radiation (NAS/NRC-BEIR)
What organization evaluates information on biological effects of radiation and provides radiation protection guidance through general recommendations on occupational and public dose limits
International Commission on Radiological Protection
Organization that reviews regulations formulated by the ICRP and decides ways to include those recommendations in US radiation protection criteria
NCRP
Organization that evaluates human and environmental ionizing radiation exposure and derives radiation risk assessments from epidemiologic data and research conclusions; provides information to organizations such as the ICRP for evaluation
UNSCEAR
Organization that reviews studies of biological effects of ionizing radiation and risk assessment and provides the information to organizations such as the ICRP for evaluation
NAS/NRC-BEIR
Objectives of the NCRP (Public Law 88-376)
1.Collect, analyze, develop and desseminate information about radiaiton measurements concerned with radiation protection
- Provide a means by which organizations may cooperate for utilization of their combined resources
- Develop basic concepts about radiation quantities and protection
- Cooperate with ICRP and other national/international organizations
US regulatory agencies
Nuclear Regulatory Commission (NRC)
Agreement states
Enivronmental Protection Agency (EPA)
US Food and Drug Administration (FDA)
Occupational Safety and Health Administration (OSHA)
Organization that oversees the nuclear energy industry, enforces radiation protection standards, publishes its rules and regulations to Title 10, and enters into agreements with state govementments that permit the state to license and regulate the use of radioisotopes and certain other material within the state
NRC
Enforce radiation protection regulations through their respective health departments
Agreeable states
Facilitiates the development and enforcement of regulations pertaining to the control of radiation in the environment
EPA
Conducts an ongoing product radiation control program, regulating the design and manufacture of electronic products, including x-ray equipment
FDA
Functions as a monitoring agency in places of employment, predominately in industry
OSHA
Facilities providing imaging services must have an effective and detailed:
Radiation safety program
Steps for implementing an effective radiation safety progarm
Begins with administration personnel
Executives must provide the resources for creating and maintaing the program
Functions of Radiation Safety Committee
Provides guidance for the program
Facilitates ongoing operation of program
Selects a qualified person to serve as a radiation safety officer
Who is responsible for the oversee of the program’s daily operations and provides for a formal review of the program each year
RSO
RSO is normally a:
Medical physicist
Health physicist
Radiologist
Qualified through experience and training
RSO has been designated by a health care facility and approved by:
NRC and the state
Develops radiation safety program that follows internationally accepted guidelines
RSO
Who grants the RSO the authority necessary to implement and enforce policies of the radiation safety program
Management of the facility
Other responsibilities of RSO:
Review and maintain monitoring records for all personnel
Be available to provide counseling
Necessary training and experience for an RSO are described in what sections of the Code of Federal Regulations:
10 CFR 35.50
10 CFR 35.900
What are the three training pathways for an RSO
Certification by one of the professional boards approved by the NRC
Didactic and work experience as described in the regulations
Identification as an authorized user, authorized medical physicist, or authorized nuclear physicist on the license, with experience in the types of uses for which the individual has RSO responsibilities
10 CFR 35.24 requires that the licensee provide the RSO:
Sufficient authority
Organizational freedom
Management prerogative to perform specific duties
A radiation safety officer in a health care facility must have sufficient authority, organizational freedom, and management prerogative to
Identify radiation safety problems
Initiate, recommend, or provide corrective action
Stop unsafe operations involving by-product material
Verify implementation of corrective actions
The authority, duties, and responsibilites of the RSO must be established in:
Writing
Why does the NRC require the name of the RSO on the facilities radioactive materials license
To ensure that licensee management has always identified a responsible, qualified person who can directly interact with the NRC during inspections and also concerning any inquiries about the facility’s safety program
Usually the RSO is a ________ employee
Full-time
Purpose of Radiaition Control for Health and Safety Act of 1968
To protect the public from the hazards of unnessary radiation exposure resulting from electronic products such as microwave ovens and picture tube colors TVs
Radiation Control for Health and Safety 1968 permitted the estatblishment of:
The Center for Devices and Radiological Health (CDRH)
CDRH falls under the jurisdiction of the:
FDA
CDRH is responsible for:
Conducting an ongoing electronic product radiation control program
What law is strictly an equipment performance standards
Law 90-602
Code of Standards for Diagnostic X-ray Equipment went into effect on:
Aug 1, 1974
ALARA concept was put forth in what year and by who
1954 by the NCRP
ALARA is also known as
Optimization
The continuation of good radiation protection programs and practicies which traditionally have been effective in keeping the average and individual exposures for monitoring workers below the limit
ALARA
To define ALARA, health care facilities ususally adopt investigational levels:
1 and 2
What type of dose-response curve is ALARA
Linear nonthreshold
What was in the FDA White Paper published in Feb 2010
Each patient should get the right imaging exam, at the right time, with the right radiation dose
What launch did the FDA announce in the White Paper
A cooperative initiative to reduce unnessesary exposure from medical imaging
What act established minimal standards for the accredidation of education programs for people who perform radiologic procedures and certification of such people
Consumer-Patient Radiation Health and Safety Act of 1981
What is the purpose of the Consumer-Patient Radiation Health and Safety Act
Ensure that standard medical and dental radiologic procedures adhere to rigorous safety precautions and standards
What reports reads “To prevent the occurrence of serious radiation-induced conditions in exposed persons and to reduce stochastic effects in exposed persons to a degree that is acceptable in relation to the benefits to the individual and to society from activities that generate such exposures”
NCRP Report No 116
Categories of radiation-induced responses
Deterministic effects
Stochastic effects
Biological somatic effects of ionizing radiation that can be directly related to the dose received
Deterministic effects
Type of effects where the severity of the biologic damage increases as the dose increases
Deterministic effects
Mutational, nonthreshold, randomly occuring biologic somatic effects
Stochasic effects
Changes to somatic cells that would affect the individual when the cells divide
Mutational
Changes to germ cells that would affect future generations
Genetic
Examples of stochasic effects
Cancer
Genetic alterations
Dose-response curves used to represent stochastic effects
Linear nonthreshold and linear quadratic
Types of early deterministic effects
Erythema
Blood changes
Epilation
ARS
Types of late deterministic effects
Cataracts
Fibrosis
Organ atrophy
Loss of parenchymal cells
Reduced fetility
Sterility
Two objectives of radiation protection
- To pevent any clinically important radiation-induced deterministic effect from occurring by adhering to dose limits that are beneath threshold levels
- To limit the risk of stochastic responses to a conservative level as weighted against societal needs, values, benefits acquired, and economic considerations
Current radiaton protection philosophy is based on the assumption that what type of relationship exists between radiation dose and biologic response
Linear nonthreshold
Ionizing radiation possesses a beneficial and a ________ potential
Destructive (benefit must outweigh the risk)
The probability of injury, ailment, or death resulting from an activity
Risk (general terms)
Possibility of inducing a radiogenic cancer or genetic defect
Risk (medical imaging)
Current method used for assessing radiation exposure and associated risk of biologic damage to radiation works and the general public
EfD Limiting System
EfD limit concerns the upper boundary dose of ionizing radiation that results in a negligible risk of:
Bodily injury or hereditary damage
EfD limits may be expressed for:
Whole-body exposure
Partial-body exposure
Exposure of individual organs
Upper limits are designed to minimize the risk to humans in terms of:
Deterministic and stochastic effects
Upper limits do not include
Natural background and medical exposure
Occupational risk is generally estimated to be a ____% chance of fatal accident over an entire career
2.5%
Mental retardation increased for fetal doses greater than:
.4 Sv
Greatest risk for radiation-induced mental retardation occured when the embryo-fetus was exposed __ to __ weeks after conception
8-15
What tissue/organs have a tissue weighting factor of .01
Bone surface
Skin
What tissue/organs have a tissue weighting factor of .05
Bladder
Breast
Liver
Esophagus
Thyroid
What tissue/organs have a tissue weighting factor of .12
Red bone marrow
Colon
Lung
Stomach
What tissue/organs have a tissue weighting factor of .20
Gonads
Annual occupational EfD limit
50 mSv
Lifetime EfD limit
Should not exceed 10 times the occupationally exposed person’s age in years
Has been designed for use in the description of population or group exposure from low doses of different sources of ionizing radiation
Collective EfD
Is determined as the product of the average EfD for an individual belonging to the exposed population or group and the number of persons exposed
Collective EfD
What is the unit used for Collective EfD
Person-sievert
Annual EfD (for general public) limit for continous or frequent exposures from artifical sources other than medical and national background radiation
1 mSv
Annual EfD limit (general public) for infrequent exposures
5 mSv
EqD for pregnant radiation workers
.5 mSv per month
5.0 mSv for entire pregnancy (after declaration)
EfD limit for any education and training of individuals under 18 is:
1 mSv annually
Dose limits for cystalline lens of the eye
150 mSv
Dose limits for localized areas of the skin, hands, and feet
500 mSv
Annual negligible individual dose is
.01 mSv/year
Personnel dosimeter readings should be well below ____ of the maximum EfD limits
1/10
What is the purpose of internal action limits in health care facilities
Meant to trigger an investigation that should uncover the reason for any unusually high exposure
Who must be an active participant in an ongoing program that is designed to prevent personnel from receiving anywhere near the maximum allowed exposures
RSO and imaging department manager
What is the radiation hormesis effect
Beneficial consequence of radiation for populations continously exposed to moderately high levels of radiation
Must ensure that the facility’s operational radiation practices are such that all people are adequately protected from unnessesary exposure
RSO
NCRP is not an __________ agency
Enforcement
Enactment of the NRCP’s recommendations lies wthin what agencies
Federal and state
NRC was formally known as:
Atomic Energy Commission
Who is responsible for regulations concerning an employee’s “right to know” about hazards
OSHA
What organization is the international authority on the safe use of sources of ionizing radation
ICRP
How many active members are in the ICRP
12
How many committees are in the ICRP
4
ICRP is not an __________ agency
Enforcement
Agency that has the authority to control the possession, use, and production of atomic energy in the interest of national security
NRC
Users of radioactive material must be licensed by:
NRC
What does NARM stand for
Naturally occurring and/or accelerator produced radioactive materials
What are NARMs
Thallium 201
Palladium 103
What are the responsibilities of the executives to run an effective radiation safety program
Delegate funds
Oversee policies and procedures
Provide equipment
Provisions for Code of Standards for Diagnostic X-ray Equipment
- PBL
- Permanent filtration
- Reproducibility and linearity
- Spot films during fluoro
- Beam on indicators
- Manual back up timers
In the US, the ALARA levels are usually __ to __ of the regulatory limits
1/10 to 3/10
Erythema and cataract formation have a high probability when entrance radiation doses exceed:
2 Gy
Rad Tech dosimeter should be below __ of max effective dose limits
1/10
