Appendix 1 - United States notification categories

United States notification categories
Category[*] Definition
Unusual event

First of four emergency classification levels, meaning that events are in process or have occurred which indicate a potential degradation of the level of safety of the plant or indicate security threat to facility protection. No releases of radioactive material requiring offsite response or monitoring are expected unless further degradation of safety systems occurs.
Alert

Second of four emergency classification levels, meaning events are in process or have occurred which involve an actual or potential substantial degradation in the level of safety of the plant or a security event that involves probable life threatening risk to site personnel or damage to site equipment because of intentional malicious dedicated efforts of a hostile act. Any releases are expected to be limited to small fractions of the U.S. Environmental Protection Agency (EPA) Protective Action Guideline (PAG) exposure level.
Site area emergency

Third of four emergency classification levels, meaning that events are in process or have occurred which involve an actual or likely major failures of plant functions needed for protection of the public or security events that result in intentional damage or malicious act: (1) toward site personnel or equipment that could lead to the likely failure of (2) prevents effective access to equipment needed for the protection of the public. Any releases are not expected to result in exposure levels which exceed U.S. EPA PAG exposure levels beyond the site boundary.
General emergency

Fourth of four emergency classification levels, meaning that events are in process or have occurred which involve actual or imminent substantial core degradation or melting with a potential for loss of containment integrity or security events that result in an actual loss of physical control of the facility. Releases can reasonably be expected to exceed U.S. EPA PAG exposure levels offsite for more than the immediate site area.

[*] In US terminology these are called Emergency Classifications. It is the responsibility of the nuclear facility to classify the onsite event and issue the appropriate notification.

Appendix 2 - Quebec Notification Categories

(Ref: Section 3.1)

Quebec Notification Categories
Level Definition
Area alert

Dangerous or potentially dangerous situation within a limited area of the power station
Station alert

Dangerous or potentially dangerous situation within an important area of the power station
General alert
Level 1

Dangerous or potentially dangerous situation with radioactive materials released to the environment

  • low risk to the population and the environment
  • no protective measures required for the population
General alert
Level 2

Dangerous or potentially dangerous situation with radioactive materials released to the environment

  • significant risk to the population and the environment
  • protective measures recommended for the population by Gentilly-2

Appendix 3 - International Atomic Energy Agency (IAEA) notifications

(Ref: Section 3.1)

1.0 General

1.1 The International Atomic Energy Agency (IAEA) sponsors a convention on Early Notification of a Nuclear Accident (which came into force in 1986). Most states with nuclear programs, including Canada, have adopted the convention.

1.2 Under the convention, signatories have agreed to notify the IAEA and other countries which could be affected in case of a nuclear emergency that could result in a transboundary radiological release. In return, the IAEA has undertaken to inform other states which may be affected.

1.3 The convention does not specify the form or content of the notification. However, the IAEA has produced an International Nuclear Event Scale (INES) and made it available to member states for adoption. States may use the INES in making notifications under the convention. The INES is described in section 3.0 below.

1.4 The convention also requires signatories to promptly provide to the IAEA and the states notified (as per paragraph 1.2 above) relevant information to assist them in dealing with the effects of the event. The IAEA will also transmit this information to affected states.

2.0 Information Required

2.1 Under Article 5 of the convention a state having a nuclear accident shall promptly provide (see paragraph 1.4 above) the following information/data as then available:

  1. The time, exact location where appropriate, and the nature of the nuclear accident.
  2. The facility or activity involved.
  3. The assumed or established cause and the foreseeable development of the nuclear accident relevant to the transboundary release of the radioactive materials.
  4. The general characteristics of the radioactive release, including, as far as is practicable and appropriate, the nature, probable physical and chemical form and the quantity, composition and effective height of the radioactive release.
  5. Information on current and forecast meteorological and hydrological conditions, necessary for forecasting the transboundary release of the radioactive materials.
  6. The results of environmental monitoring relevant to the transboundary release of the radioactive materials.
  7. The offsite protective measures taken or planned.
  8. The predicted behaviour over time of the radioactive release.

2.2 The initial information provided is to be supplemented at appropriate intervals by further relevant information as the situation develops, including the foreseeable or actual termination of the emergency.

3.0 International Nuclear Event Scale – General Description

3.1 Events are classified on the scale at seven levels; levels 1-3 are termed as 'incidents' and Levels 4-7 are termed 'accidents'. Events without safety significance are classified as 'below Scale/level 0'.

3.2 For communication of events to the public, a description has been attributed to each level of INES. In order of increasing severity, these are: anomaly, incident, serious incident, accident and local consequences, accident with wider consequencesfootnote 1, serious accident and major accident.

3.3 The structure of the scale is shown in the table below. Events are considered in terms of their impact on three different areas: impact on people and the environment; impact on radiological barriers and controls at facilities; and impact on defence in depth (with examples of past accidents). Principles of INES criteria and detailed definitions of the levels are provided in INES Manual 2008:

General criteria for rating events in international nuclear event scale

Accidents
INES level Description People and the environment Radiological barriers and controls at facilities Defence in Depth Examples
7 Major accident

Major release of radioactive material with widespread health and environmental effects requiring implementation of planned and extended countermeasures.

 n/a n/a

Chernobyl NPP, USSR (now Ukraine), 1986
6 Serious accident

Significant release of radioactive material likely to require implementation of planned countermeasures

 n/a n/a

Kyshtym Reprocessing Plant, USSR (now in Russia), 1957
5 Accident with wider consequences
  • Limited release of radioactive material likely to require implementation of some planned countermeasures
  • Several deaths from radiation
  • Severe damage to reactor core
  • Release of large quantities of radioactive material within an installation with a high probability of significant public exposure. This could arise from a major critically accident or fire
 n/a
  • Three Mile Island, USA, 1979 (criteria under Radiological Barriers and Controls at Facilities – first bullet)
  • Windscale Pile, UK, 1957 (Criteria under Radiological Barriers and Controls at Facilities – second bullet)
4 Accident with local consequences
  • Minor release of radioactive material unlikely to result in implementation of countermeasures other than local food controls
  • At least one death from radiation
  • Fuel melt or damage to fuel resulting in more than 0.1% release of core inventory
  • Release of significant quantities of radioactive material within an installation with a high probability of significant public exposure
 n/a

Tokaimura, Japan, 1999 (Criteria under People and the Environment – second bullet)
Incidents
INES level Description People and the environment Radiological barriers and controls at facilities Defence in Depth Examples
3 Serious incident
  • Exposure in excess of ten times the statutory annual limit of workers
  • Non-lethal deterministic health effect (e.g. burns) from radiation
  • Exposure rates of more than 1 Sv/hr in an operating area
  • Severe contamination in an area not expected by design, with a low probability of significant public exposure
  • Near accident at a nuclear plant with no safety provisions remaining
  • Lost of stolen highly radioactive sealed source
  • Misdelivered highly radioactive sealed source without adequate radiation procedure in place to handle it.
  • Sellafield, UK, 2005 (Criteria under Radiological Barriers and Controls at Facilities – second bullet)
  • Vandellos, Spain, 1989 (Criteria under Defence in Depth – first bullet)
2 Incident
  • Exposure of a member of the public in excess of 10 mSv.
  • Exposure if a worker in excess if the statutory annual limits.
  • Radiation levels in an operating area of more than 50 mSv/hr.
  • Significant contamination within the facility into an area not expected by design
  • Significant failure in safety provisions but with no actual consequences
  • Found highly radioactive sealed orphan source, device or transport package with safety provisions intact
  • Inadequate packaging of highly radioactive sealed source
  • Atucha,Argentina, 2005 (Criteria under People and the Environment – second bullet)
  • Cadarache, France, 1993 (Criteria under Radiological Barriers and Controls at Facilities – second bullet)
  • Forsmark, Sweden, 2006 (Criteria under Defence in Depth– first bullet)
1 Anomaly n/a n/a
  • Over-exposure of a member of the public in excess of statutory limits
  • Minor problems with safety components with significant defence in depth remaining
  • Low activity lost or stolen radioactive source, device or transport package.
 n/a

No safety significance (below scale/level 0)

Note: refs: INES Manual 2008

Footnotes

  • footnote[1] Back to paragraph For example, a release from a facility likely to result in some protective action, or several deaths resulting from an abandoned large radioactivity source. (ref: INES Manual 2008)