Q.1 Generic criteria

GC are used in the early stages of an emergency, prior to the availability of actual radiation monitoring data, when technical staff in the PEOC Scientific Section undertake dose projection modelling. GC values are calculated to reduce the risk of stochastic effects and are expressed in terms of equivalent dose (tissue or organ) and effective dose (whole body).

GC are compared against the dose projections modelled in order to determine the need for implementation of protective measures for the purposes of:

  1. exposure control
  2. ingestion control
  3. population monitoring and medical management
  4. trade control of foodstuff and other commodities
  5. protection of emergency workers.

The GC used in this PNERP are implemented based on Health Canada’s Generic Criteria and Operational Intervention Levels for Nuclear Emergency Planning and Response.

Table Q – 1: Reactor Facilities and their Designated/Host Municipalities
Projected DoseProtective Measure
50 mSv (5 rem) in the first 7 days (HT)Iodine thyroid blocking
10 mSv (1 rem) of averted dose in the first 2 days (E)Sheltering
100 mSv (10 rem) in the first 7 days (E or Hfetus)Evacuation

100 mSv (10 rem) in the first year footnote 1 (E)

Or

100 mSv in the full period of in utero development (Hfetus)

Temporary relocation
Table Q – 2: Generic Criteria for Ingestion Control Measures
Projected DoseProtective Measure

3 mSv/year (0.3 rem/year)

 

(1 mSv/year (0.1 rem/year) for each of the following categories: drinking water, milk and other foods and beverages) (E)

Restriction of distribution and ingestion of potentially contaminated:

  • Drinking water
  • Milk
  • Other foodstuffs and beverages
Table Q – 3: Generic Criteria for Population Monitoring and Medical Management
Projected DoseProtective Measure
  • 100 mSv (10 rem) in one month (E)
  • 100 mSv (10 rem) for the full period of in utero development (Hfetus)

Population monitoring

  • Internal assessment
  • Medical follow-up (health screening)
Table Q – 4: Generic Criteria for Protecting Offsite Emergency Workers
Projected DoseProtective Actions
50 mSv footnote 2 footnote 3 over the duration of the response (Hp(10) or E) footnote 4Restriction of activities for individual workers

Q.2 Operational Intervention Levels

Operational Intervention Levels (OILs) are used once radiation monitoring data is available to determine the need to implement or adjust protective measures. OILs are classified as follows:

  1. Plume exposure OILs (1γ and 2γ) are used to identify areas (beyond those for response actions that have been taken during the Urgent Response Phase) where the ground deposition of radioactive material warrants protection of the public frequenting or living in the area.
  2. Skin monitoring OIL 4 γ is used to identify individuals with enough radioactive material on the skin to warrant response actions (such as decontamination). Only the public being evacuated or relocated is expected to possibly have sufficient radioactive material on the skin to warrant response actions.
  3. Ingestion control OIL 3γ is used to identify in which areas food, milk, and drinking water may have become contaminated. Where OIL 3γ is exceeded, restrictions should be put in place until more detailed assessments can be completed.
  4. The alpha/beta screening OILs 5α and 5β are used to confirm and adjust initial restrictions on food, milk and drinking water restrictions that were enacted based on OIL 3γ. If any of these OILs are exceeded, a radionuclide-specific assessment must be undertaken.

  5. Radionuclide-specific OILs for ingestion control based on laboratory measurements are provided in Annex R. If the concentration of radionuclides in food, drinking water, or milk are exceeded, or if the summation condition is exceeded, then that item is not suitable for consumption and shall be disposed of.

    Summation condition:  

    This equation represents a condition where if the sum of the ratios of the concentrations of radionuclides in the drinking water, milk, or other food or beverage (Ci) to the radionuclide specific value of the OIL in drinking water, milk or other foods or beverages (OILi) is exceeded, then that item is not suitable for consumption.


    Where,
     

    Ci         is the concentration of radionuclide in the drinking water, milk or other foods or beverages (Bq/kg or Bq/L)
    OILi     is the radionuclide specific value of OIL for radionuclide in drinking water, milk or other foods or beverages (Bq/kg or Bq/L).

  6. The OILs have been derived for use in nuclear emergencies.
  7. The OILs used in this PNERP are adopted from Health Canada’s Generic Criteria and Operational Intervention Levels for Nuclear Emergency Planning and Response.

OILs are values that support decision-making post-release by quickly relating discrete measurements of contamination to GC, thereby identifying the need for, or confirming the adequacy of, protective actions.

The OILs presented in this section should ensure that doses do not exceed the GC in Annex Q.1. Measurements should be made in accordance with the details and timeframes provided below and using properly calibrated equipment that is fit for purpose.

Table Q – 5: Operational Intervention Levels for external exposure control
OIL #Protective ActionMeasurement DetailsLevelTimeframe for Action, Relative to Release
1γEvacuationGamma dose rate (H*(10)), 1 m from the ground1000 μSv/h (100 mrem/h)Within 24h of the beginning of exposure
2γTemporary relocationGamma dose rate (H*(10)), 1 m from the ground, measured within 10 days of reactor shutdown100 μSv/h (10 mrem/h)Initiate after evacuation
2γTemporary relocationGamma dose rate (H*(10)), 1 m from the ground, measured more than 10 days after reactor shutdown25 μSv/h (2.5 mrem/h)Initiate after evacuation
Table Q – 6: Operational Intervention Levels for ingestion control
OIL #Protective ActionMeasurement detailsLevelTimeframe for action, relative to release
3γRestriction of distribution and ingestion of potentially contaminated drinking water, milk and other foodGamma dose rate (H*(10)) at 1 m from the ground1 μSv/h (0.1 mrem/h)Implement with Exposure Control and extend within days
5αConfirm ingestion controls (with lab measurements)Gross alpha activitySee Annex QInitiate within a week to a month, depending on importance of local food and drinking water to the community
5ßConfirm ingestion controls (with lab measurements)Gross beta activity

See Annex Q

 

Initiate within a week to a month, depending on importance of local food and drinking water to the community
6Confirm ingestion controls (with lab measurements)Activity concentrations for specific radionuclidesSee Table Q – 9Initiate within a week to a month, depending on importance of local food and drinking water to the community
Table Q – 7: Operational Intervention Levels for population monitoring and medical management
OIL #Protective actionMeasurement detailsLevelTimeframe for action, relative to release
4γPersonal decontamination and/or medical follow-upSkin measurement at 10 cm from the hands and the face1 μSv/h (0.1 mrem/h)Implement concurrently with Exposure Control
Table Q – 8: Ingestion Control OILs for Alpha/Beta Screening
OILActionMeasurement detailsDrinking water (mSv/y)Milk(mSv/y)Other foods and beverages (mSv/y)
5αRestrict distribution and ingestion pending radionuclide-specific analysisGross alpha (Bq/L)113
5ßRestrict distribution and ingestion pending radionuclide-specific analysisGross beta (Bq/L)103030
Table Q – 9: Radionuclide-Specific OILs
RadionuclideSymbolDrinking Water  
(Bq/L)		Milk  
(Bq/L)		Other Foods and Beverages   
(Bq/kg)
Tritium (Hydrogen-3)3H10000030000100000
Carbon-1414C3000300010000
Sulphur-35 (inorganic sulphur)35S3000300030000
Chromium-5151Cr1000030000100000
Iron-5555Fe1000300010000
Iron-5959Fe1001001000
Cobalt-5858Co100010003000
Cobalt-6060Co1001001000
Zinc-6565Zn1001001000
Rubidium-8686Rb1003001000
Strontium-8989Sr3003001000
Strontium-9090Sr3030100
Strontium-9191Sr100001000030000
Strontium-9292Sr100001000030000
Yttrium-9090Y3000100010000
Yttrium-9191Y3003001000
Yttrium-9292Y100001000030000
Yttrium-9393Y3000300010000
Niobium-9595Nb100010003000
Zirconium-9595Zr100010003000
Zirconium-9797Zr100010003000
Molybdenum-9999Mo30001000030000
Technetium-9999Tc100100300
Technetium-99m99mTc1000100000300000
Ruthenium-103103Ru100010003000
Ruthenium-105105Ru100010000100000
Ruthenium-106106Ru100100300
Rhodium-105105Rh3000300030000
Silver-110m110mAg3003001000
Antimony-127127Sb3003003000
Antimony-129129Sb10001000030000
Tellurium-127127Te300030000100000
Tellurium-127m127mTe1000100010000
Tellurium-129129Te10000100000300000
Tellurium-129m129mTe1001001000
Tellurium-131m131mTe1000300010000
Tellurium-132132Te100010003000
Iodine-129129I103030
Iodine-131131I100100300
Iodine-132132I30001000030000
Iodine-133133I100010003000
Iodine-134134I30030000100000
Iodine-135135I100010003000
Cesium-134134Cs1003001000
Cesium-136136Cs3003003000
Cesium-137137Cs1003001000
Barium-139139Ba1000030000100000
Barium-140140Ba3003003000
Lanthanum-140140La3003003000
Lanthanum-141141La10001000030000
Lanthanum-142142La100030000100000
Cerium-141141Ce100010003000
Cerium-143143Ce100300010000
Cerium-144144Ce100100300
Praseodymium-143143Pr3003003000
Neodymium-147147Nd3003003000
Iridium-192192Ir3003003000
Uranium-235235U3030100
Neptunium-237237Np3310
Neptunium-239239Np3000300030000
Plutonium-238238Pu113
Plutonium-239239Pu113
Plutonium-240240Pu113
Plutonium-241241Pu100100300
Plutonium-242242Pu113
Plutonium-244244Pu113
Americium-241241Am1110
Curium-242242Cm3030100
Curium-244244Cm1110

 

Footnotes

  • footnote[1] Back to paragraph This is an initial value. As the response progresses, this generic criterion should be reduced.
  • footnote[2] Back to paragraph This generic criterion is not appropriate for female workers who may be pregnant. These individuals should be excluded from emergency duties that would result in a dose greater than the relevant permissible dose for non-emergency situations.
  • footnote[3] Back to paragraph While the employer is responsible for ensuring worker safety at all times, offsite emergency workers should be fully aware of the potential health risks associated with the dose they may receive, and they should accept these risks.
  • footnote[4] Back to paragraph Hp(10) = personal dose equivalent at 10 mm