Cold Chain Protocol - Vaccines and Biologics

5.  Cold Chain Management Equipment

Relevant Reference Materials:

Safe Storage of Vaccines and Biologics Requires:
  • a refrigerator
  • a freezer (for ice packs)
  • a calibrated thermometer for each refrigerator
  • a thermometer or thermostat for ambient temperature monitoring
  • “DO NOT UNPLUG” notices and “WARNING” stickers for circuit boxes
  • A back up generator, if possible

5.1.  Refrigerators for Vaccines and Biologics

Refrigerators must be selected carefully and used properly. They must be:

  • able to maintain the required storage temperatures through all seasons;
  • large enough to hold the year’s highest monthly inventory, including influenza season;
  • equipped with a calibrated min/max thermometer or data logger;
  • dedicated to storing only vaccines and biologics; and
  • in a secure location away from unauthorized personnel and public access.

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5.2.  Types of Refrigerators

Bar Fridge Units

Any style of small, single door (bar style) fridge is not recommended for the storage of vaccines and biologics. This type of fridge is unpredictable and may not maintain temperatures necessary for product stability.

Domestic Refrigerators

Domestic combination refrigerator and freezer units, though not recommended for storage of vaccines and biologics, are acceptable. Domestic refrigerators are designed for food storage and not for storage of vaccines and biologics. Precautions and fridge modifications are needed (See Modifications to Improve Domestic Fridge Temperature Stability, below).

Purpose Built (Commercial) Vaccine Refrigerators
A purpose built (commercial) vaccine refrigerator (also referred to as pharmacy, lab-style or laboratory grade refrigerator) is the standard for storing large inventories of vaccines and biologics. The advantage is that they are specifically designed to ensure better temperature regulation.

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5.3.  Modifications to Improve Domestic Fridge Temperature Stability

To ensure stability of the temperature in a domestic-type fridge follow the Magnetic Vaccine Storage Diagram (Resource 1) and:

  • Ensure no more than 50 percent (50%) of the internal volume is filled with vaccines and biologics.
  • Routinely check the door to ensure that doors are tightly closed.
  • Store full bottles of water or gel packs on empty shelves, on the bottom (or in bottom drawers) and in the door to help maintain stable temperature during frequent door opening or in the event of a power failure.
  • Keep freezer packs in the freezer compartment.
  • Minimize the number of times the door is opened to reduce temperature fluctuations.

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5.4.  Refrigerator Maintenance

Any refrigerator used to store vaccines and biologics needs to have maintenance cleaning and checks following a maintenance schedule. In the event of a refrigerator malfunction immediate steps should be taken to bring it back to working order.

A refrigerator maintenance equipment log should be kept for all refrigerators used for the storage of vaccines and biologics. Details on refrigerator maintenance, servicing and repair can be documented within the log (Resource 2: Refrigerator/Temperature Monitoring Maintenance Log).

Note: For recommendations on appropriate refrigerator maintenance, please see Appendix 1: Instructions for Refrigerator and Temperature Monitoring and Maintenance and Appendix 2: Defrosting a Refrigerator/Freezer.

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5.5.  Temperature Recording Devices

The only temperature recording devices recommended for monitoring refrigerator temperatures for vaccines and biologics are:

  • Continuous Temperature Monitors (Data Loggers):
    –    Stand alone temperature monitors that can record multiple temperatures.
    –    Accompanied by computer software that allows for downloading data.
    –    Provide an accurate picture of minimum and maximum temperatures and the time spent at each temperature.

  • Digital Min/Max Thermometers:
    –    Several types are available on the market.
    –    Each has slightly different operating instructions.
    –    It is important that the installation instruction from the unit manufacturer be followed and monitored.
Fluid-filled biosafe liquid thermometers, bi-metal stem thermometers, and household mercury thermometers are NOT recommended for the temperature monitoring of refrigerators containing Vaccines and Biologics.

Room temperature can be taken using a standard household thermometer.

In settings where continuous temperature monitoring devices are not being used, Manitoba Health recommends the use of calibrated digital min/max thermometers.

  • They show the current temperature and the minimum and maximum temperatures that have been reached since the last time the thermometer was reset.
  • It is important to manually reset the min/max thermometer each time the temperatures are recorded.
  • A limitation to min/max thermometers is that the readings do not indicate when the exposure occurred and the exact length of time of exposure.

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5.6.  Thermometer Placement

In the refrigerator compartment, the thermometer should be placed on the middle shelf adjacent to the vaccines and biologics. A thermometer should be placed in the center of the refrigerator compartment away from the coils, walls, door, floor, and fan, and the temperature probe should be placed in the vaccine box.

In the freezer, the thermometer should be placed on a box (or other item) adjacent to the vaccine so that it is in the middle of the compartment, not on the floor of the freezer.

If the thermometer indicates a temperature outside the recommended range, remove the product to an appropriate storage unit and check that the thermometer is appropriately situated.

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Communicable Disease Control (CDC)
Public Health
Manitoba Health

4th Floor - 300 Carlton St.
Winnipeg MB  R3B 3M9  CANADA

Health Links – Info Santé
204-788-8200 or 1-888-315-9257