It seems self-evident that an Ultra-Low freezer should be designed to protect stored samples from being exposed to adverse temperature conditions. Key features play a critical role in safeguarding valuable samples. There are, however, significant differences in how various Ultra-Low freezers are designed.
One of the features that is important to consider is the design of the inner doors. In addition to an outer door, Ultra-Low freezers characteristically incorporate inner doors to help protect the contents stored inside the cabinet. If the freezer has an inner door for each shelf within the unit, this creates enclosed storage compartments inside the freezer.
A primary design goal for the inner doors should be to minimize warm air and moisture from entering the compartments during door openings. Design elements that should be considered are whether and how effectively the inner doors are insulated, whether the design is sturdy enough to prevent sagging, and the use of gaskets to seal the space around the doors to prevent warm, moist air from entering the storage compartments.
Different Ultra-Low freezer models have used different approaches to sealing the inner doors, including no gaskets at all, limited sealing with single blade gaskets, and sealing but not on all four sides. In order to understand the impact of inner door gaskets, we conducted a study comparing a unit with no gaskets to one that is fully gasketed on all four sides. The study evaluated the freezer’s temperature performance in the storage compartments when the outer door is opened.Clinical and research facilities depend on Ultra-Low freezers to safeguard the integrity of precious samples. Read the white paper to find out more about the impact of inner doors on sample safety.