(For other references see the Ontario Emergency Management Glossary of Terms)

Abnormal Incident:
An abnormal occurrence that may have a significant cause and/or may lead to more serious consequences. (Source: CNSC Glossary)
Accident:
Any unintended event, including operating errors, equipment failures or other mishaps, the consequences, or potential consequences, of which are significant from the point of view of protection or safety. With respect to nuclear criticality safety, the term accidents or accident sequences means events or event sequences, including external events that lead to violation of the sub-criticality margin (that is, to exceeding the upper subcritical limit). (Source: CNSC Glossary)
Activation:
Decisions and actions taken to implement a plan, a procedure or to open an emergency operations centre. (Source: Ontario Emergency Management Glossary of Terms)
After-Action Report (AAR):
A report that documents the performance of tasks related to an emergency, exercise or planned event and, where necessary, makes recommendations for improvements. (Source: Ontario Emergency Management Glossary of Terms)
Alert (U.S. emergency classification):
Events are in progress or have occurred that involve an actual or potentially substantial degradation of the safety of the plant. Any releases of radioactive material are expected to be limited to a small fraction of the U.S. Environmental Protection Agency (EPA) Protective Action Guides (PAG) exposure levels.
Alerting:
Informing the affected population, by means of an appropriate signal, that a nuclear emergency has occurred or is about to occur.
As Low As Reasonably Achievable (ALARA):
A principle of radiation protection that holds that exposures to radiation are kept as low as reasonably achievable, social and economic factors taken into account. (Source: CNSC Glossary)
Automatic Action Zone (AAZ):
A pre-designated area immediately surrounding a reactor facility where pre- planned protective actions would be implemented on the basis of reactor facility conditions with the aim of preventing or reducing the occurrence of severe deterministic effects. (Source: Canadian Standards Association (CSA N1600, General requirements for nuclear emergency management programs)
Becquerel (Bq):
The International System of Units (SI) unit of radioactivity. One becquerel (Bq) is the activity of a quantity of radioactive material in which one nucleus decays per second. In Canada, the Bq is used instead of the non-SI unit curie (Ci). (Source: CNSC Glossary)
Beyond Design Basis Accident (BDBA):
An accident less frequent and potentially more severe, than a design-basis accident. Note: For a reactor facility, a beyond-design-basis accident may or may not involve fuel degradation. (Source: CNSC Glossary)
CANDU Reactor:
A Canadian-invented pressurized heavy-water reactor that uses heavy water (deuterium oxide) for moderator and coolant and natural uranium for fuel. “CANDU” is short for CANada Deuterium Uranium. Also called CANDU. (Source: CNSC Glossary).
Cloudshine:
Gamma radiation from radioactive materials in an airborne plume.
Communications:
Advisories, directives, information, and messages that are transmitted. (Source: Ontario Emergency Management Glossary of Terms)
Community:
A generic term that includes both municipalities and First Nations. (Source: Ontario Emergency Management Glossary of Terms)
Containment (System):
A series of physical barriers that exist between radioactive materials contained in a reactor facility and the environment. Containment usually refers only to the reactor and vacuum buildings, and integral systems such as dousing.
Contamination:
Contamination refers to nuclear or hazardous substances on surfaces, or within solids, liquids or gases (including the human body), where their presence is unintended or undesirable, or to the process giving rise to their presence in such places. (Source: CNSC Glossary)
Contingency Planning Zone (CPZ):
A pre-designated area surrounding a reactor facility, beyond the Detailed Planning Zone, where contingency planning and arrangements are made in advance, so that during a nuclear emergency, protective actions can be extended beyond the Detailed Planning Zone as required to reduce potential for exposure. (Source: CSA N1600, General requirements for nuclear emergency management programs)
Crop Control:
See Produce and Crop Control.
Declaration of Emergency:
A signed declaration made in writing by the Head of Council or the Premier of Ontario in accordance with the Emergency Management and Civil Protection Act. This declaration is usually based on a situation or an impending situation that threatens public safety, public health, the environment, critical infrastructure, property, and/or economic stability and exceeds the scope of routine community emergency response.
Notes:
Municipal Declaration of Emergency: a declaration of emergency made by the Head of Council or a municipality, based on established criteria.
Provincial Declaration of Emergency: a declaration of emergency made by the Lieutenant Governor in Council or the Premier of Ontario, based on established criteria. (Source: Provincial Glossary)
Decontamination:
Reduction or removal of radioactive contamination from materials or persons.
Design Basis Accident (DBA):
Accident conditions against which a facility is designed according to established design criteria, and for which the damage to the fuel and the release of radioactive material are kept within authorized limits. (Source: CSA N1600 – General requirements for nuclear emergency management programs)
Designated Host Municipality:
The municipality assigned responsibility in the Provincial Nuclear Emergency Response Plan for the reception and care of people evacuated from their homes in a nuclear emergency (for list see Annex A).
Designated Municipality:
A municipality in the vicinity of a reactor facility which has been designated under the Emergency Management and Civil Protection Act, as one that shall have a nuclear emergency plan (for list see Annex A).
Detailed Planning Zone:
A pre-designated area surrounding a reactor facility, incorporating the AAZ, where pre-planned protective actions are implemented as needed on the basis of reactor facility conditions, dose modelling, and environmental monitoring, with the aim of preventing or reducing the occurrence of stochastic effects. (Source: Modified from CSA N1600 – General requirements for nuclear emergency management programs)
Deterministic Effects:
Radiation-induced health effects including changes to cells and tissues that are certain to occur in an individual exposed to a radiation dose greater than some threshold dose, with a severity that increases with increasing dose. Now referred to as tissue reactions. (Source: Health Canada Glossary)
Direct Reading Dosimeter:
An active dosimeter that displays cumulative dose and dose rate while in use, and may have an alarm that sounds at a preset dose and/or dose rate
Dose:
A measure of the radiation received or “absorbed” by a target. The quantities termed absorbed dose, organ dose, equivalent dose, effective dose, committed equivalent dose or committed effective dose are used, depending on the context. The modifying terms are often omitted when they are not necessary for defining the quantity of interest.
Dose Management:
Includes administrative controls to limit doses, monitor doses and record doses received by emergency workers while fulfilling their duties related to nuclear emergency response.
Dose Projection:
The calculation of projected dose (see Projected Dose).
Dose Rate:
The amount of radiation dose which an individual would receive in a unit of time. In the context of this Plan, the measurement units are multiples or submultiples of the Sievert (or rem) per hour.
Dosimeter:
An instrument for measuring and registering total accumulated exposure to ionizing radiation.
Duty Team (PEOC ):
The PEOC Duty Team’s composition is flexible, based on the nature of the emergency response scenario. For a nuclear or radiological emergency, the Duty Team consists of Operations Section staff, Scientific Section staff, reactor facility operator representative(s), PIMS staff, and others as (and if) the emergency dictates.
Effective Dose (E):
A quantity calculated by multiplying the equivalent dose received by irradiated tissues, by a tissue specific weighting factor that reflects the risk of radiation-induced cancer to that tissue. The effective doses can then be summed to obtain the effective dose absorbed by the body.
Emergency:
A situation or an impending situation that constitutes a danger of major proportions that could result in serious harm to persons or substantial damage to property and that is caused by the forces of nature, a disease or other health risk, an accident or an act whether intentional or otherwise (EMCPA).
Emergency Bulletin:
Directions to the public on appropriate protective and other measures to be taken during a nuclear or radiological emergency, which are issued by the province and broadcast through the media.
Emergency Exposure Situation:
Emergency exposure situations arise as a result of an accident, a malicious act or other unexpected event, and require prompt action in order to avoid or to reduce adverse consequences. (Guidance on Planning for Recovery Following a Nuclear or Radiological Emergency)
Emergency Information Centre (EIC):
A designated facility that is properly equipped to monitor and co-ordinate emergency information activities including the dissemination of information to the public. (Source: Ontario Emergency Management Glossary of Terms)
Emergency Planning Zone:
The area in which implementation of operational and protective actions are or might be required during a nuclear emergency, in order to protect public health, safety, and the environment.
Emergency Public Information:
Information about an emergency that can be disseminated in anticipation of an emergency or during an emergency. It may provide situational information or directive actions to be taken by the public.
Emergency Response Organization:
A group (public, private or volunteer), trained in emergency response that may be called upon to respond to an emergency situation. (Source: Ontario Emergency Management Glossary of Terms)
Emergency Worker:
A person performing emergency services to support emergency response.
Notes:
  • Emergency workers can include the following: nuclear emergency workers required to remain in, or to enter, areas affected or likely to be affected by radiation from a nuclear emergency, and for whom special safety arrangements are required; emergency workers required to provide response outside the affected areas.
  • This does not include nuclear energy workers.
  • Emergency workers can include police, firefighters, ambulance and emergency social services workers, and other essential services.
  • Those who are registered with an authorized responding organization.
  • (Source: CSA N1600 — General requirements for nuclear emergency management programs)
Emergency Worker Centre:
A facility set up to monitor and control radiation exposure to emergency workers.
Entry Control:
The prevention of non-essential persons from entering a potentially dangerous area.
Environmental Decontamination:
Reduction or removal of radioactive contamination from the environment.
Equivalent Dose:
The absorbed dose multiplied by a weighting factor for the type of radiation giving the dose. Weighting factors for use in Canada are prescribed by the Canadian Nuclear Safety Commission. This term is also sometimes called weighted dose. Expressed in terms of sievert (or rem).
Evacuation:
A directed protective action for the controlled displacement of the population from an area which has been or might become contaminated by radioactive substances to avoid exposure. (Source: CSA N1600 — General requirements for nuclear emergency management programs)
Evacuation Centre:
A centre which provides affected people with basic human needs including accommodation, food and water. (Source: Australian Emergency Management Glossary)
Exclusion Zone:
A parcel of land within or surrounding a reactor facility on which there is no permanent dwelling and over which a licensee has the legal authority to exercise control. (Source: CNSC Glossary)
Existing Exposure Situation:
Existing exposure situations already exist when a decision on control must be taken, including prolonged exposure situations after emergencies. These situations include exposure to natural background, exposure due to residual radioactive material that derive from past practices that were never subject to regulatory control, and exposure due to the residual radioactive material deriving from a nuclear or radiological emergency. (Guidance on Planning for Recovery Following a Nuclear or Radiological Emergency)
Exposure:
The act or condition of being subject to irradiation. Exposure can be either external exposure (irradiation by sources outside the body) or internal exposure (irradiation by sources inside the body).
Exposure Control:
Emergency operations aimed at reducing or avoiding exposure to a plume or puff of radioactive material. Measures to deal with surface contamination and re-suspension might also be included.
Exposure Pathways:
The routes by which radioactive material can reach or irradiate humans.
External Notification:
The notification of organizations and agencies (not directly part of the emergency management organization) which may be affected by a nuclear or radiological emergency, or which may be required to assist in responding to it.
Food Control:
Measures taken to prevent the consumption of contaminated foods that fall outside of any other ingestion control strategy (e.g., produce and crop control, livestock control). Measures may include controlling the supply of uncontaminated foodstuffs, placing foods in storage to permit radionuclide decay, and disposal of unusable stocks.
Fuel Failure:
Any rupture of a fuel sheath such that fission products may be released. (Source: CNSC Glossary)
Gamma Radiation:
Penetrating electromagnetic radiation emitted from an atom’s nucleus. Also called gamma rays. (Source: CNSC Glossary)
General Emergency:
Events at a nuclear power plant or onboard a nuclear-powered vessel resulting in an actual or substantial risk of a release of radioactivity or radiation exposure which warrants the implementation of protective actions offsite. (Source: Health Canada Glossary)
General Emergency (U.S. Emergency Classification):
Events are in progress or have occurred that involve actual or imminent substantial core degradation or melting with potential for loss of containment integrity. Release of radioactive material can be reasonably expected to exceed PAG exposure levels offsite for more than the immediate site area.
Generic Criteria:
Expressed as a projected dose, over a specified time period, above which protective actions are recommended to reduce the risk of stochastic effects.
Government Operations Centre:
The Government Operations Centre (GOC) provides an all-hazards integrated federal emergency response to events (potential or actual, natural or human-induced, accidental or intentional) of national interest. It provides 24/7 monitoring and reporting, national-level situational awareness, warning products and integrated risk assessments, as well as national-level planning and whole-of-government response management. During periods of heightened response, the GOC is augmented by staff from other government departments/ agencies (OGD) and non-governmental organizations who physically work in the GOC and connect to it virtually.
Gray (Gy):
The International System of Units (SI) unit of measurement used to express absorbed dose. One gray is defined as the absorption of 1 joule of ionizing radiation by 1 kilogram of matter. For gamma and beta radiation, the gray is numerically equal to the sievert. (Source: CNSC Glossary)
Groundshine:
Gamma and/or beta radiation from radioactive material deposited on the ground.
Imminent Release:
A radioactive emission that will occur in 12 hours or less.
Ingestion Control:
Emergency response operations in which the main aim is to avoid or reduce the risk from ingestion of contaminated foodstuff and water.
Ingestion Planning Zone:
A pre-designated area surrounding a reactor facility where plans or arrangements are made to:
  • protect the food chain;
  • protect drinking water supplies;
  • restrict consumption and distribution of potentially contaminated produce, wild-harvested foods that are fished, foraged and hunted, milk from grazing animals, rainwater, animal feed; and
  • restrict distribution of non-food commodities until further assessments.

(Source: CSA N1600  — General requirements for nuclear emergency management programs)

Initial Notification:
The notification made by a reactor facility to provincial and/or municipal authorities upon the occurrence of an event or condition which has implications for public safety or could be of concern to these authorities. The criteria and channels for making such notification are usually described in emergency plans.
Internal Notification:
The notification by an organization to its personnel who are required to respond to an emergency.
Intervention Level:
A radiation dose above which a specific protective action is generally justified. (Source: Health Canada Glossary)
Iodine Thyroid Blocking:
The reduction or prevention of the absorption of radioiodine by the thyroid gland, which is accomplished by the intake of a stable iodine compound (such as potassium iodide) by people exposed or likely to be exposed to radioiodine.
Ionizing Radiation:
For the purposes of radiation protection, radiation capable of producing ion pairs in biological material(s). Ionizing radiation is constantly present in the environment and includes the radiation that comes from both natural and artificial sources, such as cosmic rays, terrestrial sources (radioactive elements in the soil), ambient air (radon), and internal sources (food and drink). (Source: CNSC Glossary)
Joint Information Centre:
A joint centre for the province, designated municipality, federal government, and the reactor facility or CNSC licensed facility, that is responsible for providing information on the emergency to the media and the public.
Key-Holing Strategy:
A key-holing strategy refers to a targeted approach that involves selectively evacuating specific sectors or zones based on assessed risk levels and radiation exposure. This strategy prioritizes the safety of individuals in the most affected areas while minimizing disruption and resource allocation in less impacted zones. 
By identifying and isolating critical sectors, emergency response teams can implement timely evacuation procedures, provide focused resources, and maintain effective communication with the public. The key-holing strategy aims to enhance the efficiency of evacuation operations, reduce potential contamination spread, and ensure the safety of both evacuees and emergency personnel during a nuclear incident.
Land Control:
Control on the use of contaminated land for growing food products or animal feed.
Livestock Control:
Quarantine of livestock in the affected area to prevent movement to other areas. Slaughter of such animals for food may be banned.
Megabecquerel:
106 becquerels. (Source: CNSC Glossary)
Microsievert (μSv):
One-millionth of a sievert. (Source: CNSC Glossary)
Milk Control:
Measures taken to prevent the consumption of contaminated milk in the area affected by a nuclear emergency, and its export outside the area until it has been monitored. Collection and destruction of contaminated milk may also be involved.
Millisievert (mSv):
One-thousandth of a sievert. (Source: CNSC Glossary)
Mitigate:
Actions taken to reduce the adverse impacts of an emergency or disaster. Such actions may include diversion or containment measures to lessen the impacts of a flood or a spill. (Source: Ontario Emergency Management Glossary of Terms)
Municipality:
“ Municipality” means a geographic area whose inhabitants are incorporated (Municipal Act). (Source: Ontario Emergency Management Glossary of Terms)
Notification:
Conveying to a person or an organization, by means of a message, warning of the occurrence or imminence of a nuclear or radiological emergency, usually includes some indication of the measures being taken or to be taken to respond to it.
Nuclear Emergency:
An emergency that has led to or could lead to the release of radioactive material, or exposures to uncontrolled sources of radiation, which pose, or could pose, a threat to health and safety, property, and the environment. (Source: CSA N1600 — General requirements for nuclear emergency management programs)
Nuclear Establishment:
A facility that uses, produces, processes, stores or disposes of a nuclear substance, but does not include a reactor facility. It includes, where applicable, any land, building, structures or equipment located at or forming part of the facility, and, depending on the context, the management and staff of the facility.
Nuclear Facility:
A generic term covering both nuclear establishments and reactor facilities.
Nuclear Substance:
Means:
  • deuterium, thorium, uranium or an element with an atomic number greater than 92
  • a derivative or compound of deuterium, thorium, uranium or of an element with an atomic number greater than 92
  • a radioactive nuclide
  • a substance that is prescribed as being capable of releasing nuclear energy or as being required for the production or use of nuclear energy
  • a radioactive by‑product of the development, production or use of nuclear energy
  • a radioactive substance or radioactive thing that was used for the development or production, or in connection with the use, of nuclear energy

(Source Nuclear Safety and Control Act)

Offsite:
Offsite refers to the area outside the boundary (fence) of a reactor facility.
Onsite:
Onsite refers to the area inside the boundary (fence) of a reactor facility.
Onsite Emergency:
A serious malfunction which results or may result in an atmospheric release of radioactive material or is likely to result in a release at a later time.
Operational Directive:
Direction given by the Emergency Response Organization to implement operational measures.
Operational Intervention Level (OIL):
A calculated value, measured by instruments or determined by laboratory analysis that corresponds to an intervention level.

Notes:

  • OILs are typically expressed in terms of dose rates or of activity of radioactive material released, time integrated air concentrations, ground or surface concentrations, or activity concentrations of radionuclides in environmental, food, or water samples.
  • An OIL is a type of action level that can be used immediately and directly (without further assessment) to determine the appropriate protective actions and other response actions on the basis of an environmental measurement.

(Source: Based on CSA N1600 — General requirements for nuclear emergency management programs)

Operational measures:
Measures undertaken by the Emergency Response Organization to deal with the emergency, including measures to enable or facilitate protective action for the public, e.g., public alerting, public direction, activation of plans, traffic control, emergency information, etc.
Operator:
Holder of a subsisting licence issued pursuant to the Nuclear Safety and Control Act for the operation of a reactor facility.
Optimization:
The process of determining a level of protection and safety that makes exposures and the probability and magnitude of potential exposures as low as reasonably achievable, with economic and social factors being taken into account.
Pasture control:
Measures taken to prevent animals from consuming contaminated feed and water. Measures may include removing milk- and meat-producing animals from pasture and from access to open water sources and supplying them with uncontaminated feed and water.
Personal monitoring:
The use of radiation monitoring devices to assess whether persons, and their belongings, including vehicles, are contaminated or not, and, if contaminated, the type and level of contamination.
Personal protective equipment:
Clothing or other specialised equipment provided to an offsite emergency worker to prevent or reduce their exposure to radioactive material. (Source: Health Canada Glossary)
Planned exposure situation:
Planned exposure situations involve the planned operation of a source (e.g., the operation of nuclear reactors) or planned activities that result in an exposure from a source (e.g., disposal of radioactive waste at an EWC). (Guidance on Planning for Recovery Following a Nuclear or Radiological Emergency)     
Note: See definitions for AAZ, DPZ, CPZ, and IPZ. (Source: CSA N1600, General requirements for nuclear emergency management programs)
Plume:
A cloud of airborne radioactive material that is transported in the direction of the prevailing wind from a reactor facility. A plume results from a continuing release of radioactive gases or particles. (This term may also be used for waterborne radioactive material resulting from a liquid emission. Where the context does not make it clear, this will be referred to as a waterborne plume).
Population monitoring and medical management:
The protective action strategy which includes population screening, decontamination, internal contamination assessment and medical follow-up. The purpose of this Protective Action Strategy is to reduce exposures to individuals. (Source: Health Canada Glossary)
Precautionary measures:
Measures directed to facilitate the application and effectiveness of protective measures.
Preparedness:
Actions taken prior to an emergency or disaster to ensure an effective response. These actions include the formulation of emergency response plans, business continuity/continuity of operations plans, training, exercises, and public awareness and education. (Source: Ontario Emergency Management Glossary of Terms)
Prevention:
Actions taken to stop an emergency or disaster from occurring. Such actions may include legislative controls, zoning restrictions, improved operating standards/procedures or critical infrastructure management. (Source: Ontario Emergency Management Glossary of Terms)
Probability:
The likelihood of an event occurring that may result in an emergency, disaster or service disruption. (Source: Health Canada Glossary)
Produce and crop control :
Measures taken to restrict the harvesting or processing of potentially or actually contaminated crops, vegetables and fruits. Measures include embargoing export outside the affected area; storage to allow radionuclide decay; destruction and disposal of contaminated produce
Projected dose:
The highest committed effective equivalent dose or committed equivalent dose to a specified organ or tissue, likely to be received through all applicable exposure pathways by the most exposed member of the critical group in the area for which the projection is being made.
Protective actions:
Actions to mitigate the effects of a nuclear or radiological emergency. The actions include both precautionary measures and protective measures.
Protective measures:
Measures designed to protect against exposure to radiation during a nuclear or radiological emergency. The measures include sheltering, evacuation, potassium iodide (KI) pill ingestion, ingestion control, relocation, protective clothing, and respiratory protection.
Provincial Emergency Operations Centre (PEOC):
A fully equipped facility maintained by Emergency Management Ontario that can be activated in response to, or in anticipation of, emergencies. The PEOC is staffed with appropriate representatives from ministries that have been delegated responsibilities for specified emergencies as well as EMO staff, and other partners in emergency management. It serves as a coordinating point-of-contact for the affected municipality, provincial, and federal interests. (Source: Ontario Emergency Management Glossary of Terms)
Provincial Nuclear Emergency Response Plan (PNERP):
Short title for the Strategic Response Framework for Nuclear & Radiological Emergency Management. An approved emergency response plan for the Province of Ontario to respond to a nuclear or radiological emergency, and its consequences.
Public alerting:
See Alerting.
Public awareness and education program:
A program that provides focused information to a target audience to educate about protective actions to reduce the risk of life and property damage, in the event of an emergency. (Source: Ontario Emergency Management Glossary of Terms)
Radiation:
The emission by a nuclear substance, the production using a nuclear substance, or the production at a reactor facility of, an atomic or subatomic particle or electromagnetic wave with sufficient energy for ionization. (Source: Health Canada Glossary)
Radioactive Material: For purposes of nuclear security, any material that emits one or more types of ionizing radiation, such as alpha or beta particles, neutrons or gamma rays. (Source: CNSC Glossary)
Radioactive Material:
For purposes of nuclear security, any material that emits one or more types of ionizing radiation, such as alpha or beta particles, neutrons or gamma rays. (Source: CNSC Glossary)
Radioiodine:
A substance containing radioactive iodine in a chemical form that has a metabolic pathway similar to iodide, such as inorganic compounds and metabolic forms of organic iodine that are broken down in a living organism. Some examples are the radioisotopes iodine-125 and iodine-131. (Source: CNSC Glossary)
Radioisotope:
A variation in the form of atoms, of the same chemical element, which are distinguished by the number of neutrons in the nucleus. The number of protons remains the same, but the number of neutrons differs. For example, uranium has 16 different isotopes. (Source: CNSC Glossary)
Radiological emergency:
Emergency caused by an actual or environmental hazard from ionizing radiation emitted by a source other than a reactor facility.
Radionuclide (or radioactive isotope or radioisotope):
A naturally occurring or artificially created isotope of a chemical element having an unstable nucleus that decays, emitting alpha, beta and/or gamma rays until stability is reached.
Reactor facility:
A facility producing greater than 10 megawatts gross thermal energy from nuclear fuel and consisting of one or more reactor units. Note: This includes nuclear power plants and research reactors greater than 10 megawatts gross thermal energy.
Reception Centre:
Locations for the initial reception, monitoring, decontamination, and registration of evacuated members of the public, which provides or arranges for further emergency social services, humanitarian assessments and support. 
Notes:
  • A public Reception Centre is typically located in an existing facility, such as a community centre. Public Reception Centres should be beyond the Detailed Planning Zone boundary.
  • Examples of emergency social services include emergency shelter, food, clothing, victim registration and inquiry and personal services.
  • Examples of humanitarian support include, but are not limited, to housing and family reunification. (Source: Modified IAEA Safety Guide GS-G-2.1.)
Recovery:
The short-term and long-term actions taken in order to restore, to an acceptable level, both the organizations involved in, and the communities affected by, the nuclear emergency and the associated response activities. (Source: CSA N1600 — General requirements for nuclear emergency management programs)
Release:
In the context of this plan, release refers to the emission of radioactive material to the environment from a reactor facility in the form of either an airborne or a liquid emission.
Representative individual:
An individual that due to his/her characteristics, habits and location of residence, is representative of the more highly exposed individuals in the population. May also be referred to as Representative Person. (Source: Health Canada Glossary)
Reportable event:
An event affecting the reactor facility which would be of concern to the offsite authorities responsible for public safety.
Response:
The actions taken during a nuclear or radiological emergency to reduce the magnitude of the hazard and manage its consequences, including the impact of the hazard on people, property, and the environment.
(Source: CSA N1600, General requirements for nuclear emergency management programs)
Response sectors:
The Detailed Planning Zone is subdivided into Response Sectors to facilitate the planning and implementation of protective measures.
Risk:
The product of the probability of the occurrence of a hazard and its consequences. (Source: Ontario Emergency Management Glossary of Terms)
Self-decontamination:
The removal of radioactive contamination from oneself through removal of clothing, washing of oneself and dressing in clean clothes. (Source: Centers for Disease Control and Prevention)
Severe accident:
A beyond design basis accident involving fuel degradation in the reactor core or wet storage bay.
Shall:
Is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to conform to the PNERP.
Shelter-in-place:
A directed protective action to take immediate refuge in an enclosed structure for protection from an airborne plume, deposited radioactive material, or both.
Notes:
  • Shelter-in-place is a protective action which uses the shielding properties of buildings and their potential for ventilation control to reduce the radiation dose to people inside. Shelter-in-place has varying degrees of effectiveness depending on the type of building construction.
  • Shelter-in-place should typically not extend beyond two days.
  • Shelter-in-place is utilized as a protective action if there is insufficient time to safely evacuate an area; if the dose projected for an area is so low that evacuation is not required; or the risks of evacuation are higher than shelter-in-place (e.g., severe weather inhibits safe evacuation).     
    (Source: CSA N1600 — General requirements for nuclear emergency management programs)
Should:
Is used to express a recommendation or that which is advised but not required in order to conform to the PNERP.
Shutdown state:
A subcritical reactor state with a defined margin to prevent a return to criticality without external actions. (Source: CNSC Glossary)
SI:
International System of Units; acronym from the French definition “Système International d’unités”. (Source: modified from CNSC Glossary)
Sievert:
The International System of Units (SI) unit of equivalent dose and effective dose, equal to 1 joule/ kilogram. (Source: CNSC Glossary)
Source term:
A generic term applied to the radioactive material released from a reactor facility. It includes the quantity nd type of material released as well as the timing and rate of its release. It could apply to a release that was currently occurring, or one which had ended, or one which could take place in the future.
Site area emergency (U.S. Emergency Classification):
Events are in progress or have occurred that involve actual or likely major failures of plant functions needed for protection of the public. Any releases of radioactive material are not expected to exceed PAG exposure levels, beyond the site boundary.
Stochastic effects:
Radiation-induced health effects, such as cancer and heritable diseases, which are associated with a statistical risk and where no threshold has been established. The probability of occurrence is proportional to the dose (the higher the dose the higher the probability of occurrence) but the severity of the effect is independent of dose. (Source: Health Canada Glossary)
Support municipality:
Pursuant to Section 7.0.2 (4) of the EMCPA, the LGIC may, by order, specify a municipality to act in a support capacity to provide assistance to designated municipalities.
Tissue reactions:
Radiation exposure can lead to various biological effects at the cellular and tissue levels, depending on the type, dose, and duration of exposure. Tissue reactions, also known as deterministic effects, are dose-dependent responses that manifest in specific organs or systems following exposure to ionizing radiation.
Transborder emergency:
A nuclear emergency involving a reactor facility or nuclear accident or event outside the borders of Ontario that might affect people and property in the province.
Unusual events:
(U.S. Emergency Classification): Unusual events are in progress or have occurred that indicate a potential degradation of the level of safety of the plant. No releases of radioactive material requiring offsite response or monitoring are expected unless further degradation of safety systems occurs.
Urgent protective action:
A protective action in the event of an emergency which must be taken promptly (normally within hours) in order to be effective, and the effectiveness of which will be markedly reduced if it is delayed. The most commonly considered urgent protective actions in a nuclear or radiological emergency are evacuation, decontamination of individuals, sheltering, respiratory protection, iodine prophylaxis and restriction of the consumption of potentially contaminated foodstuffs. (Source: IAEA definition)
Venting:
The release to the atmosphere of radioactive material from the containment of a reactor facility through systems designed for this purpose.
Vulnerable populations:
Members of the public who have additional needs before, during, and after a nuclear or radiological emergency in one or more functional areas.
Notes:
  • Functional areas can include, but are not limited to, the following:
    • maintaining independence;
    • communication;
    • transportation;
    • supervision; or
    • medical care.
  • Individuals in need of additional assistance could include those who:
    • have disabilities;
    • are from diverse cultures;
    • have limited or no proficiency in the local official language; or
    • are transportation disadvantaged.

(Source: CSA N1600 — General requirements for nuclear emergency management programs)

Water control:
Measures taken to avoid the contamination of drinking water supplies and sources, and to prevent or reduce the consumption of contaminated water. Measures may include the isolation of drinking water systems to prevent system-wide contamination.
Weighted dose:
See Equivalent Dose. Expressed in terms of Sievert (or rem).
Wild-harvested food:
A wild harvest represents food gathered from plants that grow naturally in an untouched environment and in their native habitat.
Wild-harvested food control:
Wild-Harvested Food Control refers to the systematic management and monitoring of food sources obtained from natural environments in the context of nuclear emergency response. This process includes the assessment of safety and contamination levels of wild-harvested foods—such as plants, mushrooms, and game—potentially impacted by nuclear incidents. It involves protocols for testing, guidelines for harvesting, and public advisories to ensure that consumption of these foods does not pose a health risk due to radioactive exposure or contamination. The objective is to safeguard public health and mitigate the risks associated with consuming wild foods in areas affected by nuclear incidents.