ICRP Glossary

The ICRP Glossary collects ICRP’s definitive explanations of terms for current use. It is a living document, updated regularly. Each entry shows the date it was last updated, and some include past glossary entries to help readers better understand the term in a particular context.

Many ICRP publications have included their own glossaries. The ICRP Glossary includes most of the terms in these other glossaries, many with updated entries. ICRP publications will continue to have their own glossaries when necessary, for example for highly specialized terms relevant to a single publication or helpful for a reader to have close at hand, or when introducing a new term which would also be added to the ICRP Glossary.

Although the ICRP Glossary is not a dictionary, terms already well covered in the Oxford English Dictionary are not included here unless further explanation is needed to understand the way in which these terms are used in ICRP publications.

The ICRP Glossary shown here comprises some 400 terms. Entries for an additional approximately 400 terms are being added progressively.

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A

B

C

D

E

F

G

H

I

J

K

L

M

N

O

P

Q

R

S

T

U

V

W

X

Y

Z

...

A

• Absolute risk

• Accelerated fractionation

• Acceptance test

• Access control

• Accountability

• Action Level

• Active (red) bone marrow

• Activity median thermodynamic diameter

• Acute exposure

• Acute radiation sickness (see *Acute radiation syndrome)

• Acute radiation syndrome

• Adaptive response

• Additive risk projection model

• Adventitious

• Adventitious source

• Aerodynamic diameter

• Air-kerma rate constant

• Air-kerma, entrance surface

• Air-kerma, incident

• Air-kerma, product

• Alimentary tract

• Alimentary tract transfer factor

• Alpha decay

• Alveolar-interstitial region

• Angiogenesis

• Annihilation photons

• Annual dose

• Area monitoring

• ARS (see Acute radiation syndrome)

• Attributable risk

• Auger transition

• Authorised discharge

• Authorization

• Authorized limit

• Autoimmune disease

• Autonomy

• Averted dose

B

• Background dose (rate)

• Backscatter factor

• Basal cell

• Baseline disease rates

• BAT (see Best available techniques)

• Beneficence

• Benthic

• Best available techniques

• Beta-minus decay

• Beta-plus decay

• Bioassay

• Biomarker

• Biomedical research volunteer

• Bioturbation

• Bone marrow

• Bradycardia

• Branching fraction

• Bronchial region

• Bystander effect

C

• Cardiac arrhythmias

• Cardiac valve diseases

• Cardiomyopathy

• Cardioverter-defibrillator

• Case–control study

• Cell death

• Chronic exposure

• Class SR-0 gases

• Class SR-1 gases

• Class SR-2 gases

• Clearance level

• Clonogenic cells

• Clonogenic survival

• Co-expertise

• Cohort study

• Colony

• Committed effective dose

• Committed equivalent dose

• Complex tissues

• Computed tomography dose index

• Connective tissue

• Consequential late effects

• Constancy test

• Contamination

• Coronary heart disease

• Cost-benefit analysis

• Coster-Kronig transition

• Curie

• Cytokines

D

• DD (see Doubling dose)

• DDREF (see Dose and dose-rate effectiveness factor)

• Decay constant

• Decommissioning

• Decontamination

• Decontamination factor

• Deontological Ethics

• Deterministic effect

• Detriment

• Detriment-adjusted risk

• Diastasis

• Dicentric chromosome

• Dichotomous

• Differentiation

• Dignity

• Direct bioassay

• Disposal

• Disposal facility

• DNA damage signalling

• Dose and dose-rate effectiveness factor

• Dose constraint

• Dose criteria

• Dose equivalent in an organ or tissue

• Dose limit

• Dose modifying factor

• Dose per unit intake coefficient

• Dose rate

• Dose rate effectiveness factor

• Dose-threshold hypothesis

• Dose-rate effect

• Dose–response function

• Dose-threshold

• Doubling dose

E

• EAR (see Excess absolute risk)

• Early normal tissue responses

• Edema

• Effect Dose 50

• Effect modifier

• Effective charge number

• Effective dose equivalent

• Effective half-life

• Electron-capture decay

• Electrophysiology

• Elemental dose

• ELR (i.e. Excess Lifetime Risk, see Lifetime risk estimates)

• Emergency

• Emergency exposure situation

• Emergency plan

• Emergency preparedness

• Emergency procedures

• Endogeneous excretion

• Epigenetic effects

• Environmental exposure

• Environmental radiation protection

• Epithelium

• Equity

• Equivalent dose

• ERR (see Excess relative risk)

• Erythropoietin

• Ethics

• Excess absolute risk

• Excess lifetime risk (see Lifetime risk estimates)

• Excess relative risk

• Excretion rate (instantaneous)

• Exempt waste

• Exemption level

• Existing exposure situation

• Exponential survival curve

• Exposure, external or internal

• Exposure pathway

• Exposure situation

• Extrathoracic airways

F

• Fairness

• Field-size effect (Volume effect)

• Flexible tissues

• Fluoroscopically guided interventions

• Forbiddenness

• Fractionation

• Fractionation sensitivity

G

• Galactic cosmic radiation

• Gamma ray

• Gastrointestinal syndrome

• Genomic integrity

• Graded approach

• Granulocyte colony-stimulating factor

• Granulocyte-macrophage colony-stimulating factor

• Growth fraction

• Growth hormone (somatotropin)

H

• Habitual mouth breather

• Habitual nose breather

• Half-life, physical

• Hazard

• Health Surveillance

• Heliosphere

• Hereditary effect

• Hierarchical tissues

• High level waste

• Homologous recombination

• Hormones

• Human respiratory tract model

• Hyperbaric oxygen

• Hypertrophic cardiomyopathy

• Hypoplasia

I

• Immune system

• In vivo radiobioassay

• Incidence

• Incidence rate (see Incidence)

• Incident

• Inclusiveness

• Individual decontamination

• Individual monitoring

• Individual-related

• Induced genomic instability

• Informed consent

• Inhalability

• Inner bremsstrahlung

• Institutional control

• Intermediate level waste

• Internal conversion electron

• Interphase death

• Intervention Level

• Interventional procedure

• Investigation level

• Iso-effect plots

• Isomers

• Isotropic geometry

• Itinerant (radiation) worker

J

• Justice

• Justification

K

• Kp index

L

• Late normal tissue responses

• Latent time/period or latency interval

• LD_50/30

• Life Span Study

• Lifetime risk

• Lifetime risk estimates

• Limitation of dose

• Lineal energy

• Linear dose response

• Linear-non-threshold model

• Linear-quadratic dose response model

• LLE (see Lifetime risk estimates)

• Loss of Life Expectancy (see Lifetime risk estimates)

• Low Earth orbit

• Low dose

• Low dose rate

• Low level waste

• LSS (see Life Span Study)

• Lymphatic system

M

• Macrophage colony stimulating factor

• Magnetosphere

• Medical exposure

• Member of the public

• Mendelian diseases

• Mitigation

• Multiplicative risk projection model

• Multistage carcinogenesis model

• Multistage tumorigenesis

• Mutation component

• Myocardial perfusion

• Myocardial stress test

N

• Naturally occurring radioactive material

• Necrosis

• Neurological syndrome

• Neurovascular syndrome

• NHEJ (see Non-homologous end joining)

• Nominal risk coefficient

• Non-homologous end joining

• Non-maleficence

• Non-sphericity parameter

• Non-targeted effects

• Normal tissue complication probability

• Nuclear track detectors

O

• Occupational exposure

• Oncogene

• Optimisation

• Orphan source

• Oversight

P

• Particle radiance

• Patient entrance reference point

• Peak skin dose

• Pelagic

• Percutaneous coronary intervention

• Pericarditis

• Pharynx

• Planned exposure situation

• Platelet-derived growth factor

• PLDR (see Potentially lethal damage repair)

• Pooled analysis

• Population risk

• Potential exposure

• Potentially lethal damage repair

• Practical radiological protection culture

• Prevailing circumstances

• Principle of application of dose limits

• Principle of justification

• Principle of optimisation

• Procedural values

• Progenitor cell

• Programmed cell death

• Projected dose

• Protection strategy

• Protective action

• Protective action guide

• Prudence

• Public exposure

Q

• Qualified expert

• Quasi-threshold dose

R

• Radiation belt

• Radiation detriment (see Detriment)

• Radiation modifier

• Radiation risk

• Radiation safety officer

• Radiation Source

• Radiation worker

• Radioactive dispersion device

• Radioactive source

• Radioactive substance

• Radioactivity

• Radiofrequency ablation

• Radiographer

• Radiological controlled area

• Radiological protection principles

• Radionuclides of natural origin

• Radioresponsiveness

• Radiosensitiser

• Radiosensitivity, cellular

• RAP (see Reference Animal and Plant)

• RBE (see Relative biological effectiveness)

• Reactive oxygen species

• Reasonableness

• Recovery

• Recovery responder

• Recovery (cellular or tissue)

• Reference Animal and Plant

• Reference bioassay function

• Reference biokinetic model

• Reference level

• REID (see Lifetime risk estimates)

• Rehabilitation of living conditions

• Relative biological effectiveness

• Relative life lost

• Relative risk

• Relocation

• Remedial action

• Remediation

• Repopulation

• Representative organism (non-human biota)

• Representative person

• Reproductive integrity

• Residual dose

• Respiratory protection

• Retrievability

• Reversibility

• Right to know

• Rigidity threshold

• Rigidity

• Ring chromosome

• Risk

• Risk coefficient

• Risk model

• Risk of exposure-induced death

• ROS (see Reactive oxygen species)

• Routine monitoring

• RR (see Relative risk)

S

• Safety case

• Safety culture

• Scintigraphy

• Self-help protection

• Senescence

• Severe deterministic injury

• SLDR (see Sublethal damage repair)

• Slow repair

• Solar cosmic radiation

• Solar cycle

• Solar particle event

• Solar wind

• Somatic effect

• Source term

• Source-related

• South Atlantic anomaly

• Special (non-routine) monitoring

• Spontaneous fission

• Stakeholder

• Stenosis

• Stochastic effect

• Storage

• Subcutaneous tissue

• Sublethal damage repair

• Substantial radiation dose level

• Supervised area

• Systemic model

T

• Tachycardia

• Target region

• Target tissue

• Targeted effects

• Telangiectasia

• Threshold dose for tissue reactions

• Thyroid blocking

• Time factor

• Tissue equivalent material

• Tissue reaction

• Tissue weighting factor

• Tolerability

• Track structure

• Transfer compartment

• Transfer of risk

• Transfer rate

• Transforming growth factor

• Transgenerational effect

• Translocation

• Transparency

• Transport of risk (see Transfer of risk)

• Tumour suppressor gene

• Trapped particles

• Types of materials

U

• Unsealed source

• Utilitarian ethics

V

• Value judgement

• Valvular heart disease

• Virtue ethics

W

• Waste disposal

• Wisdom

• w_T (see Tissue weighting factor)

• w_R (see Radiation weighting factor)

X

• X ray

• Xerostomia

Y

Z

...

• α/β value

• α/β ratio (see α/β value)

• γH2AX foci