Glossary - NORM Worker Training

The amount of energy deposited by radiation in a unit mass of material, measured in gray (Gy) or rad.

An internal exposure pathway in which radioactive material enters the body directly through a cut, abrasion, or other break in the skin.

The amount of radioactivity per unit mass or volume of a material, typically expressed in becquerels per gram (Bq/g) or becquerels per litre (Bq/L).

Under 29 CFR 1910.1096(e)(4), an area where airborne radioactive material concentrations exceed a specified limit, or 25% of that limit averaged over the occupied hours in a week, triggering a posting requirement.

The principle that radiation exposure should be kept as low as reasonably achievable, considering economic and social factors, even when doses are already within regulatory limits.

A relatively large, positively charged particle emitted from the nucleus of certain radioactive atoms; it has very low penetrating power but can be a serious hazard if inhaled or ingested.

The level of respiratory protection that a properly functioning, correctly fitted respirator class is expected to provide to a population of trained users, expressed as a ratio of outside to inside contaminant concentration.

A deterministic effect resulting from a high, whole-body radiation dose received over a short period, producing symptoms such as nausea, fatigue, and reduced blood cell counts.

A respirator that removes contaminants from the air by passing it through a filter, cartridge, or canister before it is inhaled.

A respirator that supplies breathable air from a source independent of the surrounding atmosphere, such as an SCBA or SAR, rather than filtering ambient air.

The SI unit of radioactivity, equal to one radioactive decay (disintegration) per second.

A high-speed electron or positron emitted from the nucleus of certain radioactive atoms; more penetrating than an alpha particle but less penetrating than gamma radiation.

In the transport of NORM, the party responsible for carriage of the consignment, including proper stowage, interim storage, and radiation protection during transit.

The removal of material or equipment from regulatory control entirely, once it has been verified to meet the applicable clearance criteria.

The government body legally authorized to regulate radiation safety within a country, including licensing, inspection, and enforcement.

The person or organization sending a radioactive material package, responsible for correct packaging, labelling, and accurate documentation.

An area subject to specific rules for radiation protection purposes, requiring measures to control normal exposures and prevent or limit the likelihood and magnitude of potential exposures.

A traditional (non-SI) unit of radioactivity, equal to 3.7 x 10^10 disintegrations per second; largely superseded by the becquerel.

The sequence of radioactive decays a parent radionuclide undergoes, through a series of daughter radionuclides, until a stable (non-radioactive) nuclide is reached.

A biological effect of radiation that has a dose threshold below which it does not occur, and whose severity increases with dose above that threshold, such as skin erythema or cataracts.

A prospective, source-related restriction on the dose an individual may receive from a specific source, used as a planning tool to support optimization.

Absorbed dose adjusted for the relative biological effectiveness of the type of radiation involved, measured in sievert (Sv) or rem.

A device worn by a worker to measure and record the radiation dose the wearer receives over time.

A calculated dose quantity that accounts for both the radiosensitivity of different tissues and the type of radiation involved, allowing doses from different exposure situations to be compared on a common scale.

A feature on some respirator cartridges (typically organic vapor or gas cartridges) that signals when the cartridge is approaching saturation and needs to be changed.

Removal of a practice or source from some or all aspects of regulatory control, because the associated risk is judged to be negligible.

A category of exposure situation, under IAEA GSR Part 3, that already exists when a decision on control needs to be taken, such as exposure from a legacy NORM site; managed using a reference level rather than a dose limit.

Exposure to radiation from a source located outside the body.

Fine particulate captured from furnace off-gas during metal or mineral processing, which can carry elevated concentrations of volatile radionuclides such as lead-210 and polonium-210.

Highly penetrating electromagnetic radiation emitted from the nucleus of certain radioactive atoms, requiring dense shielding materials such as lead or concrete to reduce exposure.

The principle that regulatory requirements should be proportionate to the magnitude of the potential radiological risk, so that low-risk practices carry a lighter regulatory burden than high-risk practices.

The SI unit of absorbed dose, equal to one joule of energy deposited per kilogram of matter.

The time required for half of the atoms in a quantity of a radionuclide to decay.

A high-efficiency particulate air filter capable of capturing at least 99.97% of airborne particles of a specified size, commonly used for NORM particulate filtration.

A ranked framework for controlling hazards, generally prioritizing elimination and engineering controls over administrative controls and personal protective equipment.

IAEA General Safety Requirements Part 3, Radiation Protection and Safety of Radiation Sources: International Basic Safety Standards, which establishes the international framework for exemption, clearance, and occupational and public protection requirements, including for NORM.

IAEA Safety Guide No. GSG-7, Occupational Radiation Protection, which provides detailed recommendations for implementing GSR Part 3 requirements on occupational exposure, including the graded approach.

IAEA Safety Guide No. GSG-15, Remediation Strategy and Process for Areas Affected by Past Activities or Events, the current guidance on remediating legacy NORM sites.

IAEA Specific Safety Requirements No. SSR-6, Regulations for the Safe Transport of Radioactive Material, commonly called the Transport Regulations.

An atmospheric concentration of a hazard high enough to pose an immediate threat to life, impair the ability to escape, or cause irreversible health effects; IDLH conditions require air-supplying respiratory protection.

An internal exposure pathway in which radioactive material is swallowed, often as a result of poor hygiene practices.

An internal exposure pathway in which radioactive material is breathed into the respiratory tract, generally the pathway of greatest concern in NORM operations.

Exposure to radiation from a source located inside the body, following inhalation, ingestion, or absorption through a wound.

Radiation with enough energy to remove tightly bound electrons from atoms, creating ions; includes alpha, beta, gamma, X-ray, and neutron radiation.

An area affected by past activities involving NORM, often abandoned or of uncertain ownership, that can present an exposure pathway today even though no current operator or license exists.

A form of regulatory authorization involving a site- or activity-specific safety case, tailored conditions, and formal approval before operating, generally applied to higher-risk practices under the graded approach.

A dose-response model, used for stochastic effects, assuming risk increases linearly with dose and that no dose is completely risk-free; the basis for most current occupational and public dose limits.

A ventilation approach that captures a contaminant close to the point it is generated, using a hood or enclosure, before it can disperse into the general work area.

Radioactive material which, by its nature, has a limited specific activity, or for which limits on estimated average specific activity apply; classified as LSA-I, LSA-II, or LSA-III for transport purposes.

The highest airborne concentration of a hazardous substance from which a respirator is expected to protect the wearer, calculated as the Assigned Protection Factor multiplied by the applicable exposure limit.

Radiation consisting of neutrons, uncharged particles capable of penetrating most materials and requiring hydrogen-rich shielding, such as water or concrete, for effective attenuation.

Radioactive elements, principally from the uranium-238 and thorium-232 decay series and potassium-40, that occur naturally in the earth's crust and can become concentrated by industrial processes.

A form of regulatory authorization involving informing the competent authority that an activity is taking place and meeting basic, generic conditions, generally applied to lower-risk practices under the graded approach.

The splitting of a heavy atomic nucleus into two lighter nuclei, releasing energy; distinct from the radioactive decay processes that generate most NORM.

An integrated management plan addressing all identified workplace hazards, radiological and non-radiological, within a single compliance framework.

OSHA's Ionizing Radiation standard for general industry, establishing U.S. occupational dose limits, survey, monitoring, signage, instruction, recordkeeping, and incident-reporting requirements.

OSHA's Ionizing Radiation standard for construction work, applying the general industry ionizing radiation requirements to construction activities.

An atmosphere with an oxygen concentration below the level needed to safely sustain normal activity, generally requiring air-supplying respiratory protection rather than an air-purifying respirator.

A NIOSH-certified particulate filter rated for 99.97% filtration efficiency and rated oil-proof, generally the appropriate filter class for NORM particulate exposure.

Equipment worn to minimize a worker's exposure to a hazard, such as respirators, protective clothing, and gloves, selected based on the specific hazards of the task.

A small, wearable instrument that alerts the wearer to the presence of elevated radiation levels.

A gypsum byproduct generated in large volumes during phosphoric acid production, carrying moderately elevated radium-226 concentrations.

A qualified medical professional responsible for evaluating a worker's fitness to wear a respirator.

A category of exposure situation, under IAEA GSR Part 3, involving the deliberate introduction and operation of a source, controlled through dose limits established before operations begin.

An air-purifying respirator that uses a battery-powered blower to draw air through a filter, providing a higher assigned protection factor and reduced breathing resistance compared to a non-powered APR.

Water brought to the surface during oil and gas production, which can carry a wide range of NORM activity concentrations, principally radium-226.

An individual recognized as having the appropriate training and experience to provide advice on radiation protection matters within a facility's Radiation Protection Program.

A traditional (non-SI) unit of absorbed dose, equal to 0.01 gray; largely superseded by the gray.

A fixed radiation detection system, often installed at a facility gate or checkpoint, used to screen vehicles, equipment, or material for radioactive content.

A facility's organized, documented system for managing radiation safety, including monitoring, training, area classification, and audit and review.

A survey instrument capable of identifying specific radionuclides present in a source, in addition to measuring radiation levels.

An atom with an unstable nucleus that undergoes radioactive decay, emitting radiation in the process.

The relative susceptibility of cells, tissues, or organs to damage from ionizing radiation; generally higher for rapidly dividing, less differentiated cells.

The alkaline residue generated by digesting bauxite in sodium hydroxide during aluminium production, carrying low but present levels of NORM.

In an existing exposure situation, the dose or risk level above which it is judged inappropriate to allow exposures to occur, used to guide optimization of protective actions.

A form of regulatory authorization involving generic, pre-defined conditions for a moderate, well-understood level of risk, sitting between notification and licensing under the graded approach.

A traditional (non-SI) unit of dose equivalent, equal to 0.01 sievert; largely superseded by the sievert.

Material remaining from a process that comprises, or is contaminated by, NORM; a residue may be recycled or used as a by-product, or it may become NORM waste if no further use is foreseen.

A NORM-bearing deposit, most often containing radium-226, that forms on the interior surfaces of pipes, valves, pumps, and vessels as water chemistry changes during processes such as oil and gas production.

A condition in a decay chain where each radionuclide in the chain decays at the same rate it is produced, so all members of the chain have equal activity.

An air-supplying respirator in which the wearer carries their own compressed air supply, used for IDLH or oxygen-deficient atmospheres.

The SI unit of dose equivalent and effective dose, incorporating adjustments for radiation type and tissue sensitivity.

A solid by-product of smelting processes that can carry elevated NORM activity concentrations depending on the ore and process involved.

A semi-solid NORM-bearing residue, such as material generated during water treatment or oil and gas production, typically requiring different management than a dry solid residue.

A biological effect of radiation, such as cancer, assumed to have no dose threshold, whose probability (but not severity) increases with dose.

An area not designated as a controlled area but where occupational exposure conditions are kept under review, even though specific protective measures are not normally needed.

An air-supplying respirator connected by a hose to a remote air source, rather than a wearer-carried air cylinder.

A solid object which is not itself radioactive but which has radioactive material distributed on its surfaces; classified as SCO-I or SCO-II for transport purposes.

The residual material remaining after the valuable fraction of an ore has been extracted through mining and mineral processing, which can carry elevated NORM activity concentrations.

NORM whose radionuclide concentrations or exposure potential have been increased above natural background levels by human activity, such as processing or industrial use.

A number assigned to a radioactive material package for transport, calculated as the maximum dose rate at one metre from the package, in mSv/h, multiplied by 100.

U.S. legislation establishing a dedicated regulatory framework for uranium and thorium mill tailings, implemented through EPA standards at 40 CFR Part 192 and NRC/Agreement State licensing at 10 CFR Part 40.

A four-digit number assigned to a dangerous good, including classes of radioactive material, for identification during transport.

A ventilation strategy that reduces contaminant concentration by exchanging or diluting the air in a space as a whole, as distinct from local exhaust ventilation.

NORM for which no further use is foreseen; a subset of NORM residue that has not been, and will not be, recycled or reused.

Rock removed during mining to access ore, generated in large quantities and potentially carrying a significant radionuclide content depending on the deposit.

Penetrating electromagnetic radiation similar to gamma radiation but typically produced by electron transitions or machine sources rather than nuclear decay.