| Note:
Terms that are institution-specific are marked (Stanford) or (VAPAHCS). |
| absorbed
dose |
The energy imparted by ionizing
radiation per unit mass of irradiated material. The units of absorbed
dose are the rad and the gray
(Gy). |
| activity |
Rate of disintegration, transformation,
or decay of radioactive material. The units of activity are the curie
(Ci) and the becquerel (Bq). |
| ALARA |
Acronym for "as low as
reasonably achievable." Make every reasonable effort to maintain
exposures to radiation as far below the dose
limits as is practical consistent with the purpose for which the activity
is undertaken, taking into account he state of technology, the economics
of improvements in relation to benefits to the public health and safety,
and other societal and socioeconomic considerations, and in relation
to utilization of ionizing radiation
in the public interest. |
Annual
Limit
on Intake (ALI) |
The amount of a radionuclide
that would result in a committed effective
dose equivalent of 5 rems, or a committed dose
equivalent of 50 rems to an organ or tissue. See 10
CFR Part 20 Appendix B. |
| A&MM |
Acquisition & Materials
Management (VAPAHCS). |
| APLAC |
Administrative Panel on Laboratory
Animal Care (Stanford). |
| APRS
|
Administrative Panel on Radiological
Safety (Stanford). Other organizations may use Radiation Safety Committee
or Radiation Control Board, for example. |
| area
of use |
A room or suite in which radioactive
materials is used. It may have one or more work
areas. |
| background
radiation |
Radiation from cosmic sources;
naturally occurring radioactive materials, including radon (except
as a decay product of source or special nuclear material) and global
fallout as it exists in the environment from the testing of nuclear
explosive devices. "Background radiation" does not include
radiation from source, byproduct, or special nuclear materials, or
devices regulated by the NRC or DHS. |
| becquerel
(Bq) |
1 nuclear transformation per
second (s-1). |
| bioassa |
The determination of kinds,
quantities or concentrations, and, in some cases, the locations of
radioactive material in the human body, whether by direct measurement,
called in vivo counting, or by analysis and evaluation of materials
excreted or removed from the human body. |
| CC |
California Code of Regulations. |
| CF |
Code
of Federal Regulations. |
| controlled
are |
An area, outside of a restricted
area but inside the site boundary, access to which can be limited
by the licensee for any reason. |
| cp |
Counts per minute. Most radiation
detectors display the number of events detected per unit of time.
This can be converted to a measure of activity
in dpm by dividing by the detection efficiency. |
| CRA |
Controlled Radiation Authorization
(Stanford and VAPAHCS). The permit issued by
the APRS or RSO that allows
the use of ionizing radiation. |
| CRS |
Clinical Radiation Safety
Committee (Stanford). |
| curie
(Ci) |
A unit of activity.
3.7 x 1010 nuclear transformations per second, 3.7 x 1010
becquerels, or 2.22x1012
nuclear transformations per minute. The term nuclear transformations
is often replaced by the term disintegrations. |
| DAC |
Derived Air Concentration.
The concentration of a given radionuclide that, if inhaled continuously
during the work year, would cause a dose of 5
rem. |
| deep
dose |
The dose
from external whole body exposure at a tissue depth of 1 cm. |
| deterministic
effect |
Health effects, the severity
of which varies with the dose and for which a
threshold is believed to exist. Radiation-induced cataract formation
is an example of a deterministic effect. Also called a nonstochastic
effect. |
| DHS |
Department
of Health Services. The California agency that regulates radioactive
materials and radiation devices at non-federal facilities in the state. |
| DLAM |
School of Medicine, Division
of Laboratory Animal Medicine (obsolete). Now the Department
of Comparative Medicine. |
dose
or
radiation dose |
Generic term that means absorbed
dose, dose equivalent,
effective dose equivalent,
committed dose equivalent, committed effective dose
equivalent, or total effective dose equivalent, as defined elsewhere
in this glossary. |
| dpm |
Disintegrations per minute.
A measure of activity. See curie. |
| DTSC |
Department of Toxic Substance
Control. The California agency that regulates hazardous materials
other than radiation. |
| effective
dose equivalent or effective dose |
The sum of the products of
the dose equivalent to each organ or tissue and multiplied by their
respective tissue weighting factors,
and then added to the external whole body dose. |
| EPA |
US
Environmental Protection Agency. |
| exposure |
Being exposed to ionizing
radiation or to radioactive material. |
| external
dose |
That portion of the dose
equivalent received from radiation sources outside the body. |
| extremity |
Hand, elbow, arm below the
elbow, foot, knee, or leg below the knee. |
| FDA |
US
Food and Drug Administration. |
| gray
(Gy) |
SI unit of absorbed
dose. One gray is equal to an absorbed dose of 1 joule/kilogram
(100 rads). |
Hazards
Evaluation |
A document prepared by Health
Physics that analyzes the potential risk of a project and imposes
safety measures (Stanford). Other organizations may use the terms
license, authorization, or permit. See sample
Hazards Evaluation in the Appendix. |
high
radiation
area |
An area, accessible to individuals,
in which radiation levels could result in an individual receiving
a dose equivalent in excess
of 0.1 rem (1 mSv) in 1 hour at 30 centimeters
from the radiation source or from any surface that the radiation penetrates. |
| house
waste |
Office and lounge waste such
as paper and food containers that is normally discarded in a sanitary
landfill (Stanford). |
| HUC |
School of Medicine Radioisotope
Committee (Human Use Committee) (Stanford; obsolete. See CRSC). |
| ICRP |
International
Commission on Radiological Protection. |
| ionizing
radiation |
Alpha particles, beta particles,
gamma rays, x-rays, neutrons, high-speed electrons, high-speed protons,
and other particles capable of separating a target atom into an electron
and a positive ion. As used in this manual, radiation does not include
non-ionizing radiation, such as radio- or microwaves, or visible,
infrared, or ultraviolet light. |
| IRB |
Institutional Review Board
(National Institutes of Health).
A committee that reviews and approves research projects that involve
human subjects. At Stanford, the Administrative Panel on Human Subjects
in Medical Research performs this function. |
| LAS |
Low activity
source (Stanford). An authorization to use small amounts of radionuclides,
less than the LAS quantity.
|
| LCC |
Local Control Committee (Stanford).
The LCC oversees radiation safety within a department or school. See
CRSC and RSC. |
| LSPCH |
Lucile
Salter Packard Children’s Hospital. |
| monitoring |
The measurement of radiation
levels, concentrations, surface area concentrations or quantities
of radioactive material and the use of the results of these measurements
to evaluate potential exposures and doses. |
| NCRP |
National
Council on Radiation Protection and Measurements. A non-profit
corporation chartered by Congress to disseminate radiation protection
guidance. |
| nonstochastic
effect |
Obsolete. See deterministic
effect. |
| NRC |
US
Nuclear Regulatory Commission. The federal agency that regulates
the use of radioactive byproduct materials. It does not have authority
over accelerator-produced radioactive materials or x-rays. It also
does not have authority in California, except at federal agencies;
authority over non-federal organizations was transferred to DHS. |
| occupational
dose |
The dose
received by an individual in a restricted
area or in the course of employment in which the individual’s
assigned duties involve exposure to radiation
and to radioactive material from licensed and unlicensed sources of
radiation, whether in the possession of the licensee or other person.
Occupational dose does not include dose received from background
radiation, as a patient from medical practices, from voluntary
participation in medical research programs, or as a member of the
general public. |
| photon |
A quantum of radiant energy.
In this manual, the term usually means gamma rays or x-rays. |
| PO |
Purchase Order. |
| public
dose |
Dose received
by a member of the public from exposure to
radiation and to radioactive material released by a licensee, or to
another source of radiation either within a licensee’s controlled
area or in unrestricted areas.
It does not include occupational dose
or doses received from background
radiation, as a patient from medical practices, or from voluntary
participation in medical research programs. |
| quality
factor |
A modifying factor used to
convert dose in rad to dose
equivalent in rem. For x-, beta-, and gamma-radiation
its value is 1. |
| rad |
Special unit of absorbed
dose. One rad is equal to an absorbed dose of 100 ergs/gram or
0.01 joule/kilogram. 100 rads equal 1 gray.
(See the conversion table in the Appendix) |
| radiation
area |
An area, accessible to individuals,
in which radiation levels could result in an individual receiving
a dose equivalent in excess
of 0.005 rem (0.05 mSv) in 1 hour at 30 centimeters
from the radiation source or from any surface that the radiation penetrates. |
| RAF |
Research Animal Facility (Stanford). |
| RDRC |
Radioactive Drug Research
Committee (Food and Drug Administration).
The RDRC is chartered by the Food and Drug Administration to review
and approve basic research projects involving the administration of
radioactive drugs to human subjects. CRSC provides
this service. |
| rem |
The special unit of any of
the quantities expressed as dose
equivalent. The dose equivalent in rems is equal to the absorbed
dose in rads multiplied by the quality
factor. For most forms of radiation, one rem is numerically equal
to one roentgen or one rad.
One sievert equals 100 rems. (See the conversion
table in the Appendix) |
| restricted
area |
An area, access to which is
limited by the licensee for purpose of protecting individuals against
undue risk from exposure to radiation and
radioactive material. |
| roentgen
(R) |
The special unit of radiation
exposure. The amount of exposure that liberates
one esu of charge per cc of air. For most forms of radiation, one
roentgen is numerically equal to one rem or one
rad. Although considered obsolete, this term and
its abbreviation are still commonly used. |
| RSC |
Radiation Safety Committee.
This service is provided by the APRS and the LCCs. |
| RSO |
Radiation Safety Officer.
The individual responsible for managing the radiation safety or health
physics program. |
| Safety data sheet (SDS) |
A one-page information sheet
developed at Stanford that provides decay scheme and precautions for
a single radionuclide. (See Safety
Data Sheets in the Appendix.) |
| SHS |
Stanford
Health Services. A separate institutional entity that includes
the Stanford University Hospital and Stanford Clinic. |
| sievert (Sv) |
SI unit of any of the quantities
expressed as dose equivalent.
The dose equivalent in sieverts is equal to the absorbed
dose in grays multiplied by the quality
factor. 1 sievert equals 100 rems. (See the
conversion table in the Appendix) |
| SLAC |
Stanford
Linear Accelerator Center. |
| stochastic effects |
Health effects that occur
randomly and for which the probability of the effect occurring, rather
than its severity, is assumed to be a linear function of dose without
threshold. Hereditary effects and cancer incidence are examples of
stochastic effects. |
| SUH |
Stanford University Hospital,
now SHS. |
| survey |
An evaluation of the radiological conditions and
potential hazards incident to the production, use, transfer, release,
disposal or presence of radioactive material or other sources of
radiation. When appropriate, such an evaluation includes a physical
survey of the location of radioactive material and measurements
or calculations of levels of radiation, or concentrations or quantities
of radioactive material present.
|
| tissue
weighting factor |
A weighting factor for an
organ or tissue relating to the proportion of the risk of stochastic
effects resulting from irradiation of that organ or tissue to the
total risk of stochastic effects when the whole body is irradiated
uniformly. |
| unrestricted
area |
An area, access to which is
neither limited nor controlled by the licensee. |
| VAPAHCS |
Veterans
Affairs Palo Alto Health Care Service. |
| VMO |
Veterinary Medical Officer
(VAPAHCS). |
| VMU |
Veterinary Medical Unit (VAPAHCS). |
| VSC |
Veterinary Service Center
(Stanford). |
| work
area |
A portion of a room or laboratory
suite where radioactive materials are stored or handled. It is usually
a single countertop. |
| worker |
An individual engaged in activities
that are licensed by a regulatory agency and controlled by a licensee.
Classification as a worker does not require an employer/employee relationship.
Volunteers, students on clinical rotation, residents, staff, faculty,
and visiting scientists and physicians whose duties include work in
radiation or radioactive materials areas are considered workers. |