This document discusses the cold chain system used to store and transport vaccines. It explains that vaccines must be kept within a temperature range of 2-8 degrees Celsius to remain potent. Some vaccines like oral polio vaccine require storage at -20 degrees. The document outlines the different types of equipment used at various levels of the cold chain including walk-in cold rooms, deep freezers, ice lined refrigerators, cold boxes, vaccine carriers, day carriers, and ice packs. It provides details on the storage temperatures and capacities of each component to ensure vaccines remain effective from manufacturer to point of vaccination.

1. COLD CHAIN
Presented By:
Mrs. Precilla B. Thoppil
Associate Professor

2. Introduction
‘Cold chain’ is a system of storage and transport of vaccines at optimum
temperature (2-8 degree) from manufacturer to the site of vaccination.
This cold chain is needed because vaccines are sensitive to heat and
they may lose their potency if not stored and transported at optimum
temperature. Among all vaccines, oral polio vaccine is the most heat
sensitive vaccine, requiring storage -20 degree.

4. Storage of vaccine
A. Vaccines to be stored in freezer • OPV
• MEASLES
B. Vaccines to be stored in cold part of
refrigerator but not freezer
• TYPHOID
• DPT
• DT
• BCG
• TT
C. Vaccine that can be kept at room
temperature
• TT

5. Equipment of cold chain system
1. Walk – in – Cold Rooms
Walk-in cold rooms are located at the regional levels and are
meant to store vaccine supplies for up to 3 months. They are
used to store vaccine supply of 4-5 districts

6. 2. Deep freezers (300 Lts)and Ice Lined Refrigerator
ILR(300/240Lts capacity)
• Deep freezers and ice lined refrigerators are supplied to all
districts and walk-in-coldrooms to store vaccines. Deep
freezers are used for making ice packs and for storing OPV
and measles vaccines.

7. 3. COLD BOXES
• Cold boxes are supplied to all peripheral vaccination centers. These
boxes are of different sizes usually 5 litres and 20 litres. A 5 liter cold
box can hold one month vaccine supply of a primary health center.
They are also used for transportation of vaccines. Fully frozen ice
packs are placed at the bottom and sides of cold boxes. The vaccines
are first wrapped in polythene bags and then kept inside cold boxes.

8. 4. VACCINE CARRIER
• Vaccine carriers are used to carry small quantity of vaccines
(16-20 vials) for outreach sessions. It is a square box made up of
insulated material. Four fully frozen ice packs are used to line
the sides. The vaccine carrier should be closed tightly. It has a
working capacity of 48 hours.

9. 5. DAY CARRIER
• These are square boxes containing 2 ice packs, one placed at
bottom and other at top of the box. They are used to carry
small quantities of vaccines I6-8 vials) to a nearby session. It
has a working capacity of 12 hours.

10. 6. ICE PACKS
• The ice packs contain water and no salt is added to it.
Water is filled up to the marked level and it is allowed
to freeze.