Proper Equipment – Chamber Comparison

Can I use a food grade refrigerator as a stability chamber?  In visit to a stability lab recently, I noted a labeled 5 C chamber that was a restaurant grade unit.  In an effort to save dollars, the purchasing group found a refrigerator that would meet the needs of the facility in their opinion.  But did it meet the needs?  In review below, I compared a pharma grade chamber, a food grade chamber and a laboratory grade chamber to show the differences.  Here is a comparison.

Pharma grade PI Food grade PI Laboratory grade PI
Operating temperature 2 – 70°C +33°F to +38°F (0.6 to 3.3 C) X 1°C to 8°C
Claimed uniformity ± 1.0°C

(± 1.8°F)

Not listed X Not listed X
Exterior measurement 82″ x 34.5″ x 91.5″ 78 1⁄8″ x 29 1⁄2″x 84 1⁄8″ 85” x 37.2” x  79.2”
Interior Measurement 75″ x 28.5″ x 60″) Not listed X 81” x 29” x  58”
Interior cu. ft. 74.2 72.0 78.8
Compressor ½ hp ½ hp ½ hp
Defrost Schedulable Not listed X Automated X
Defrost configurable Yes No X No X
Controller Digital controller Preset X Limited digital
Controller security Yes No X Yes partial X
Electrical 208-230V/1ph/60hz 115V 60Hz 115V 60Hz
Alarm notification Yes No X Yes
Total of PI 0 8 4

PI – Potential Issue

After looking at the table above you can see that the pharma grade chamber has the additional engineering added to it, to justify the higher cost.  The question now is do I really want to place my product in a chamber that is not designed for the process it is doing?  Do you use something that is labeled for a restaurant or a laboratory use as a stability chamber?  Inspecting auditors know what these units intended use is, and may look at other areas to see if cost cutting was done that may impact the quality of the product.

In reach-in chambers the placement of shelving is usually left as-received/as-validated positions unless a larger item needs to be added.  At that point did you do a risk assessment on the change in the configuration?  Was your initial validation sufficient to cover a minor adjustment of a shelf?  Does your validation policy cover shelving rearrangement and discusses what is a minor and major change?  These questions are potential 483 issues depending on your inspecting agent.

In the design of walk-in chambers, are you obtaining the maximum amount of shelving when you install a new chamber?  I reviewed a couple of quotes and noted that they contained drawings of shelving placement.  In these drawings, the vendor used a standard fixed pattern setup.  In these drawings only approximately 40% of the interior chamber volume was being used for storage.  Will this percentage meet you intend design requirements?  The rest of the space was walkways and support space.   This is a waste of unused space, if you do a cost analysis of this part of the project.  There is several high density shelving products on the market. which can add up to an additional 25 to 30% more space depending on the size of your chamber.

High density shelving is validated in the same method as fixed shelving use.  The use of high density shelving can lead to a question by an auditor if shelving is replaced back in the same position as they were originally validated in.  This question can be answered a couple of different ways.  The first is training of personnel to return to the same location as an operational practice.  This becomes time consuming as you are required to prove the fact with documentation, I.E. One person signs and a second person signs as verification of the return to the original position in a logbook.  The second is the developing of additional data through validation runs to show that shelving placement does not affect the performance.  These runs can be added at the beginning of the chamber validation process or gained through scheduled validations to show there is no impact.

If you have any questions, feel free to ask us


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