CBRN Glossary
Plain definitions of the chemical, biological, radiological and nuclear terms used across training, detection and response.
C
- CBRN
- Chemical, Biological, Radiological and Nuclear — the family of hazards arising from the release of toxic chemicals, pathogens or radioactive and nuclear material, whether deliberate or accidental. CBRN domains →
- CBRNe
- CBRN with the addition of explosives, used where explosive devices may disperse or accompany chemical, biological or radioactive material.
- Chemical warfare agent (CWA)
- A toxic chemical used, or produced for use, as a weapon. Classes include nerve agents (G- and V-series), blister agents such as sulphur mustard, and blood and choking agents. Chemical domain →
- CLYC
- Cs₂LiYCl₆:Ce, a scintillator that detects both gamma rays and neutrons in a single crystal, making gamma-neutron detection possible in compact instruments.
- Committed effective dose
- The total effective dose a person will receive from radioactive material taken into the body, integrated over 50 years for adults. MS-DIE →
- Continuous air monitor (CAM)
- An instrument that continuously samples air and measures airborne radioactivity, typically alpha- and beta-emitting aerosols, alarming when concentrations rise. MS-CAM →
D
- Decontamination
- Removing or neutralising contamination on people, equipment and infrastructure. It ranges from immediate and operational (hasty) measures to thorough and technical decontamination.
- Dosimeter
- An instrument that measures the radiation dose received by a person or an object.
E
- Electronic personal dosimeter (EPD)
- A direct-reading dosimeter worn by a worker that displays accumulated dose and dose rate, and alarms at set thresholds. MS-EPD4 →
G
- Geiger–Müller tube
- A gas-filled detector that produces a pulse for each ionising event. Robust and simple, it is widely used for dose-rate measurement but gives no energy information.
H
- HazMat
- Hazardous materials: substances that pose a risk to health, property or the environment during transport, storage or an incident, and the civilian response discipline that deals with them. HazMat training →
- Hp(10)
- Personal dose equivalent at a depth of 10 mm in soft tissue — the operational quantity used by personal dosimeters to estimate effective dose from penetrating radiation.
I
- Improvised nuclear device (IND)
- A crude nuclear explosive built from diverted fissile material and capable of producing a nuclear yield.
L
- Live-agent training
- Training with real toxic chemicals or radioactive sources under controlled conditions at certified facilities, within internationally accepted occupational exposure limits. Live-agent training →
N
- NORM
- Naturally occurring radioactive material — such as potassium-40 and the thorium and uranium decay series — found in building materials, fertilisers and some goods, and a common source of nuisance alarms.
O
- Occupational exposure limit (OEL)
- The maximum concentration of a hazardous substance in workplace air, averaged over a reference period, to which workers may be exposed without adverse health effects.
P
- Personal protective equipment (PPE)
- Suits, respirators, gloves and boots that protect the wearer from exposure. In CBRN response, PPE is selected according to the hazard and the level of protection required.
- Personal radiation detector (PRD)
- A small, wearable alarming instrument that detects gamma — and in some models neutron — radiation, used by responders and security staff. Performance criteria are set by ANSI N42.32. PRD guide →
R
- Radiological dispersal device (RDD)
- A device that uses conventional explosives or other means to spread radioactive material, without producing a nuclear explosion. Often called a “dirty bomb”.
- Radionuclide identification
- Determining which radioactive isotopes are present by analysing the energy spectrum of the gamma rays they emit.
- Radon progeny
- The short-lived radioactive decay products of radon gas. They attach to airborne particles, and air monitors must compensate for them to avoid false alarms.
S
- Scintillation detector
- A detector in which radiation produces flashes of light in a crystal or plastic that are converted into an electrical signal. Common scintillators include CsI(Tl), NaI(Tl), LaBr₃ and CLYC.
- Sievert (Sv)
- The SI unit of equivalent and effective dose, reflecting the biological effect of radiation. Working values are usually expressed in millisieverts (mSv) or microsieverts (µSv).
- Special nuclear material (SNM)
- Plutonium, and uranium enriched in the isotopes U-233 or U-235 — material whose detection is a priority in nuclear security.
- Spectroscopic personal radiation detector (SPRD)
- A personal radiation detector that also records gamma-ray spectra in order to identify radionuclides. Performance criteria are set by ANSI N42.48. PRD guide →
T
- Toxic industrial chemical (TIC)
- A chemical produced or used in industry that is toxic enough to cause harm if released, such as chlorine or ammonia.
- Toxic industrial material (TIM)
- A broader term covering toxic industrial chemicals together with biological and radiological materials used in industry.
U
- Unmanned aerial vehicle (UAV)
- A drone. In CBRN work, UAVs carry detectors for aerial reconnaissance and mapping of contamination. MS-UAV-ARR →
- Unmanned ground vehicle (UGV)
- A remotely operated or autonomous ground robot that carries sensors, cameras or payloads into hazardous areas. MS-CBRN-RR →
- Unmanned surface vessel (USV)
- An uncrewed boat used for monitoring, sampling and reconnaissance on water. MS-UCF →