What is a Laboratory Refrigerator?

Medical professionals and researchers are using laboratory refrigerators to preserve vaccines, medicines, and biological specimens within specified temperature ranges.

Equipping a laboratory refrigerator is one of the top priorities in every healthcare facility. The refrigerator’s purpose is to keep a variety of fluids and substances in a regulated space so that they are stored in specified temperature conditions – which will reduce the risk of possible contamination and destruction of hazardous items. In order to achieve this, consistent temperatures must be maintained. To accomplish this high level of accurate temperature control, the refrigerator needs to have proper internal airflow and ventilation at all times.

How is a laboratory refrigerator different from a domestic refrigerator?

Despite the fact that both units are designed to keep their contents cold, differences exist in their usage and maintenance requirements.

Household refrigerators are used in storing edible products such milk, cheese, fruits, vegetables, etc. These units are not given much care after they are switched on; and the foods and other edible contents inside do not necessarily have be organized. On the other hand, the function of laboratory refrigerators is to keep biological items, such as vaccines, medicines, blood samples, breast milk supplies, etc., within carefully specified temperatures. Unlike domestic refrigerators, laboratory refrigeration units require proper content positioning (inside the refrigerator), daily calibration and maintenance, and constant temperature monitoring.

Laboratory refrigerators are classified into four types:

• Explosion-proof units are devised to be functional in areas where air surrounding the unit is very likely to be flammable. This also includes combustible liquids and hazardous substances with breaking points of less than 100°F (37.7°C).   

• Laboratory refrigerators are built with digital controllers, glass door, and alarm systems – which mainly help in the monitoring and regulation of temperatures. This type refrigerator meets the regulatory requirements of laboratory research.

• Blood bank refrigerators are one of the most essential units in every immunohematology department. This type refrigerator allows whole blood, blood elements (such as blood cells and plasma), and blood compounds to be safely and easily stored while making sure they are kept fresh. Blood bank refrigerators are not only known for its reliability but also for their ability to efficiently monitor temperatures.

• Chromatography refrigerators are designed for research experiment purposes. It is best to use this type of refrigerator in laboratories that require accurate temperature settings and consistency for their medical samples and procedures.

Laboratory refrigeration units also come with special features including:

Wide range of sizes

Each laboratory facility has its own size requirement for its refrigerators – which will depend on how much storage it needs and how spacious the room is for the installation.  As a result, laboratory refrigerators of varying sizes (from small to medium to large) have been designed. Small refrigerators are very compact so they can be placed on a countertop or underneath a desk, while medium-sized refrigerators are about as big as a household dishwasher.

Accurate temperature control and display

Laboratory refrigerators generally operate from 2°C to 10°C (35.6°F to 50°F), although there are exceptions. The control settings of a laboratory refrigeration unit have a range starting from a simple dial thermostat (cold, colder, coldest) to a stylish digital display, which allows its users to program accurate logic controls.

Also, for faster shutdown and recovery instances, features such as bypass refrigeration and microprocessor-based controls are provided in some laboratory refrigerators. 

In order for the unit to avoid any increase in the temperature, a rear-wall plenum and heatsink on either the plenum or the surface are provided.

Efficient temperature recording and alarms

Every single laboratory refrigerator is tailored with a thermometer and an alarm that gives off warning sounds if the temperature exceeds the limit of its specified range. This thermometer monitors both the temperature of the air inside the refrigerator and includes a second glycine probe which imitates the temperature of the contents inside the unit – providing a more precise temperature measurement of the refrigerator’s stored contents.

Adjustable designs

Due to limitations of floor space in various laboratories, it has been made possible for laboratory refrigerators to be designed and fit under laboratory counters.  They can also be mounted on a wall, or integrated with another unit. 

The doors of a laboratory refrigeration unit can also be either solid or sliding glass, depending on the contents that will be stored inside (such as narcotics or clinical samples).

As well as doors and the basic design, but also shelves are designed for adjustment.  Normally, metals such as aluminum and stainless steel are used as shelves in a refrigeration unit; as the industry develops shelf materials are changing. Now, most refrigerators are equipped with shelves made of coated wire, which makes them more easily-washable and more hygienic. A lot of refrigerators also have separate internal cabinets that can help eliminate cross-contamination of samples and substances and stop unauthorized handling of delicate items.

Secured locks

Laboratory refrigerators are equipped with security locks as a standard solution for the unauthorized use of the unit.  This feature is important as:

• It keeps the medicines and vaccines safe from theft
• It prevents access to potentially hazardous specimens.

Refrigerator-Freezer Option

A stand-alone laboratory refrigerator can also be fitted with a freezer. This kind of unit also comes with features including thermometers, alarms, and displays, however, it does more freezing than cooling.

To further understand how a laboratory refrigerator operates, listed below are some of the guidelines on the use of the unit:

• All samples or reference materials should be sealed inside plastic pouches or standard vials. These items should not be exposed, to prevent cross-infection due to proximity among other samples.

• Samples that are light-sensitive should be stored in dark bags or amber-tinted vials.

• Chemicals, foods, and pharmaceutical items should be stored in their specified temperature range appropriate for their storage requirements. It is not recommended to place sample in any available space, as that will reduce the efficiency of the refrigeration system.

• Cabinets should be labeled and sample locations should be kept updated through user records. This practice will save effort and time in finding samples and standards when needed.