The needs of refrigeration can vary from holding a sample for intense study and exams during a period at a steady temperature, or just saving the sample and other important things on a normal but cold temperature. Having the right refrigerator or freezer is extremely important when thinking about sample and specimen storage. If the temperature fluctuates, the risk of damaging vaccines, for example, is very high.
You need the right laboratory refrigerator and freezer to storage life-saving materials in your laboratory. Refrigerators and freezers are used to cool and preserve samples, specimens, store plasma and blood products, vaccines and other medical and pharmaceutical supplies. In contrast to the ones using for domestic purpose, e.g. at home or restaurant, freezers and refrigerators should be reliable and hygienic.
Laboratory refrigerators and freezers have separate compartments that isolate samples to avoid cross-contamination.
Types of refrigerators
Laboratory refrigerators operate from 2°C to 10°C, and temperature can be displayed and selected with a simple dial or a sophisticated LED, depending on the model. There are four basic types of refrigerators:
– Explosion-proof refrigerators: they can store flammable liquids and hazardous chemical samples. This equipment may have been designed to avoid combustion in the storage area.
– Basic Laboratory refrigerators: They can maintain consistent temperatures and monitor the temperatures with digital displays. They are used to cool samples and for their preservation.
– Blood bank refrigerators: Keeping cool whole blood and/or its components, it is a delicate matter. It is important to have the right temperature, measurements, structure, cooling system and control system. That is why reliability is critical for this type of refrigerator. This type of refrigerator has also separate compartments for storing different sample types.
– Chromatography refrigerators: are designed for a variety of applications and research experiments. They are the ideal refrigerators for laboratories where medical samples and procedures require precise temperature settings and stability. They also have full access to chromatography instrumentation.
Freezers
There are three basic types of laboratory freezers:
– General purpose freezer: with pre-set temperatures between -20 and -30 °C.
– Low-temperature freezer: with pre-set temperatures between -30 and -45 °C.
– Ultra low freezer: with pre-set temperatures between -45 and -86 °C.
How to choose the right freezer or refrigerator
There are some basic features to bear in mind when buying a refrigerator or freezer:
1. Configuration. There is some basic configuration:
– Upright. They have the advantage of having more shelves and is easy to visualize the organization. The biggest freezers and refrigerators have additional storage in the door. There are compact models, the under-counter, which are ideal for storing materials that the user needs frequently and they can be placed near the workstation to be at hand. The disadvantage of this model lies in the temperature. When the door is opened, the temperature rises and it is difficult to maintain. On the other hand, the use of the storage in the door is that the temperature fluctuates and may affect the items.
– Chest freezers: the disadvantage of this type of freezer is the difficulty to organise them, for example, if the user needs something from the bottom, he/she has to move other items from the top. However, they are capable of storing larger material and temperature control is much easier.
2. Combination of freezer and refrigerator: Although they have separate doors, the advantage of these models is that they use the space of a unit having both functions. These are especially for labs with little space.
3. Size: There are models with different depth, width and high. It all depends on the space available and the capacity the user needs.
4. Temperature control: Some samples need precise temperature requirements so researchers have to bear in mind this detail when choosing the right freezer or refrigerator.
5. External alarm: To prevent a possible failure, it is important that the equipment has an external alarm to alert malfunctioning or temperature variations that may affect the items.
6. Defrost: There are two types of defrosting: manual and automatic.
– Manual Defrost: on this case, when defrost is needed, the items in the freezer must be removed while the defrosting process and be relocated temporarily in another freezer.
– Automatic defrost: although this system is very practical because it changes the temperature of the freezer to remove the ice on the walls, the materials in the freezer can be at risk. On this type of defrosting system, it is advisable to keep these units full enough to prevent changes of temperature that causes ice on the walls. This type of units requires more energy than the manual.
7. Material visibility: this type of refrigerator or freezer has insulated glass door (used in upright freezers), but they are very practical because it can be easily seen what it is inside
Anecdotes
Freon gas R22 (CH-CI-F2) is a refrigerant that has been used in refrigeration systems and as it is considered CFC, its use was restricted since 1987 in order to preserve the ozone layer.
Frequently Asked Questions
How to save energy?
To save energy there are some basic tips to follow:
– Keep the refrigerator or freezer away from heat sources.
– Allow air circulating, especially at the back of the equipment.
– Keep clean the door seal and dust coils behind the refrigerator.
– Label items to localize them rapidly.
Why are temperature sensors important?
In some areas, like medical and pharmaceutical, it is important to document temperature for validation and it is necessary to have a data-logging sensor to collect data.
Kalstein products offer a wide range of options when it comes to storage at low temperatures. There is a variety of medical refrigerator and freezers for the laboratory. You can find different kinds of cooling systems in our catalog HERE
