Laboratory freezers are designed for storing critical materials that demand a constant temperature and security. They include units for freezing blood plasma and other blood products, as well as laboratory equipment for storing vaccines and other medical or pharmaceutical supplies. Some laboratory freezers are designed to fit under a laboratory counter. Larger stand-alone units are also available. Laboratory freezers that comply with regulations from agencies such as the U.S. Food and Drug Administration (FDA) are designed to provide specific levels of temperature control and a uniform temperature throughout the chamber. Reduced humidity laboratory freezers are designed for seed storage and applications in which the freezer doors are opened and closed frequently.
Most laboratory freezers are equipped with one or more solid doors or sliding glass doors. These units differ in terms of size, materials of construction, finish style and color. Typically, the adjustable shelves in laboratory freezers are made of metals such as aluminum and stainless steel. Products with shelves made of coated wire are also available. By design, most freezer shelves are washdown-capable, sanitary, or hygienic. For faster pull-down and recovery times, some laboratory freezers are equipped with features such as bypass refrigeration and microprocessor-based controls. A rear-wall plenum and heatsink on either the plenum or the floor can help to limit the temperature rise. Low-humidity laboratory freezers minimize moisture in the ambient air. Chamber capacity and temperature range are important specifications to consider.
Some laboratory freezers include special instrumentation for conducting experiments that require strict temperature control. For example, a lab freezer can be used to set up a chromatography apparatus within the chamber. Laboratory freezers that are designed for blood banks must be able to maintain the quality of the blood supply. Lab freezers that store blood and blood products usually meet a variety of regulatory and quality standards, and typically come with an alarm system to warn laboratory personnel if the equipment fails. Units may be fitted with locks to restrict entry, and may even be designed to safely insulate flammable materials from electrical sparks. Pharmacies and pharmaceutical companies use laboratory freezers to store vaccines, medications, and other temperature-sensitive compounds.