How to use Freezers and Refrigerators

What seems to be easy to answer is not necessarily always the case, according to a blog published by the U.K. Medicines and Healthcare Products Regulatory Agency MHRA. This post is in fact a very good article describing some of the main issues with freezers used by pharmaceutical wholesalers.

It starts with purchasing the right equipment. What needs to be considered when buying a freezer is the following:

• Intended use (e.g. conditioning and storing cold packs or frozen medicinal products)
• Temperature range needed
• Size
• Defrost options
• Easy to clean
• Robustness
• Speed of freezing/ cooling cold packs

The freezer should be fully qualified in line with GDP qualification requirements before use.  The whole installation should "include risk assessment of the impact of the installation, e.g. effect of heat generation by the freezer on the surrounding area". The Personnel should be trained and user restrictions should be considered.

Storage of medicines

There are not many medicines that require storage in a freezer. So, according to MHRA, "there is often a temptation to use the same freezer for other purposes such as conditioning of cold packs", which might be a risk for the products. MHRA recommends using dedicated freezers for storing medicines, considering that "not all frozen medicines require storage at the same frozen temperature".

Combined refrigerator/freezer units might also have some risks because "if one unit becomes non-functional then the both units are compromised".

Conditioning of cold packs

When conditioning cold packs, several points need to be considered:

• The use of the correct type of pack (e.g. -80°C, -15°C, +5°C, +25°C)
• The use of different phase change materials (PCM)
• Appropriate qualification
• When is the cold pack fully conditioned?

MHRA also delivers some tips for the use of cold packs:

• "Only use packs in the way defined by the manufacturer or qualification exercise
• Prevent mix-up of conditioned and non-conditioned packs e.g. by numbering them or managing how they are conditioned such as rotation of freezers used for conditioning
• If supercooling is a problem then consider conditioning the pack at the storage temperature e.g. for a pack used at 5°C, condition in a refrigerator rather than in a freezer
• Prevent mix-up of different types of pack e.g. 0°C and 5°C by either minimising the varieties of pack used or storing separately
• Check the condition of pack for damage before each use
• Store in clean conditions"

Get more details in the MHRA Inspectorate Blog Post "Use of Freezers".