Cold Chain Protocol - Vaccines and Biologics



Appendix 4: Algorithm to Assess Problems in Temperature Readings

The following algorithms summarizes actions to be taken if the refrigerator temperature reading is less than +2ºC or greater than +8ºC.

Temperature reading is < +2ºC
  1. Is the thermometer properly placed and working?
No

Move the thermometer/probe to the centre of the middle shelf. Change battery, if necessary.

Yes
   
  1. Is the thermostat set to an appropriate setting?
No

Adjust the thermostat to a warmer setting. Recheck the temperature of the refrigerator every half hour until the temperature stabilizes at or around +5ºC. Continue to monitor for several more hours.

Yes
   
  1. Has the ambient temperature of the room become warmer?
Yes

Adjust the temperature of the room so that it is not too warm. A warm room will cause the refrigerator to work harder, producing a cooler environment inside the refrigerator.

No
   
  1. Is there good air circulation outside of the refrigerator?
No

Ensure the refrigerator is set up according to the recommended clearance requirements and that nothing is impairing the air exchange around the unit.

Yes
   
  1. Call a trained technician to check the refrigerator.
 

 

Temperature reading is > +8ºC
After ensuring that the refrigerator is plugged in, the outlet is working and/or the cord is functioning properly:

  1. Is there electrical power to the refrigerator?
No

Check the fuse box then contact the electric or hydro company in your area (if necessary).

Yes
   
  1. Is the door closed properly?
No

Check the levelling legs, door seals, door latch and hinges. Call a technician to repair as necessary.

Yes
   
  1. Is the thermometer properly placed and working?
No

Move the thermometer/probe to the centre of the middle shelf. Change battery if necessary.

Yes
   
  1. Is the thermostat set to an appropriate setting?
No

Adjust the thermostat to a colder setting. Recheck the thermometer every half hour until the temperature stabilizes at or around +5ºC. Continue to monitor for several more hours.

Yes
   
  1. Has the ambient temperature of the room become cooler?
Yes

Adjust the temperature of the room so that it is not too cold. A cold room will cause a cool ambient temperature outside and a warm environment inside of the refrigerator.

No
   
  1. Is there good air circulation inside and outside of the unit?
No

Rearrange vaccine trays to allow air to circulate around the vaccines. Ensure that nothing is impairing the air exchange around the unit.

Yes
   
  1. Call a trained technician to check the refrigerator.
   

Adapted from the First Nations Inuit Health Branch, Health Canada and CDC Vaccine Storage and Handling Toolkit (2005), Resources Section, National Vaccine Storage and Handling Guidelines for Immunization Providers, Appendices.

Note: If a simple solution to a cold chain problem is not immediately identified (power disconnected, fridge door ajar, temperature probe misplacement, etc.) move vaccines and biologics to a back-up refrigerator or temporarily store in Styrofoam coolers.

Communicable Disease Control (CDC)
Public Health
Manitoba Health, Seniors and Active Living

4th Floor - 300 Carlton St.
Winnipeg MB  R3B 3M9  CANADA
Phone: 204-788-6737
Fax: 204-948-2040