A laboratory freezer often protects valuable medical or scientific materials that may be the basis of your laboratory operations. With such an important function, the laboratory freezer you choose must be reliable, have accurate temperature control and be the right type to suit your laboratory’s requirements.
Laboratory freezers come in different types divided by temperature and configuration.
The temperature
There are three common temperature categories of laboratory freezer including general purpose with preset temperatures between -20 and -30 degrees C, low temperature with preset temperatures between -30 and -45 degrees C and ultra low temperature with pre -Temperatures set between -45 and -86 degrees C. All preset temperatures are adjustable, but only within a narrow range, so it’s important that the freezers you’re considering match your temperature requirements.
Configuration
Laboratory freezers come in two common configurations; straight and chest. Elevated routes can be further divided into free and lower.
Right freezer
Upright freezers have the advantage of easier organization. Usually upright freezers have more shelves and you can move items around in the fridge without having to remove other items that may be on top.
Larger drivers also usually have extra door space, which provides additional flexibility to store frequently used materials for quick access when needed.
Upright under counter freezers are especially good for storing smaller items that you need frequent access to because they can be placed out of the way near the workstation that uses them.
The disadvantage of upright freezers lies in temperature control. When you open an upright freezer, cold air wants to flow out of the freezer. The drop in temperature can be dramatic making it more difficult to maintain the desired temperature. The more times you have to open the door to perform laboratory operations, the more pronounced the effect will be.
Something to consider when buying an upright lab freezer is the internal compartment doors. Especially for temperature-sensitive materials, interior compartment doors allow you to more precisely control the temperature for those items protected by the doors. The temperature in the remainder of the compartment may fluctuate more with the opening and closing of the main door, while the materials behind the interior doors of the compartment remain constant or close to constant.
Another feature of some freezers is the ability to adjust the temperature automatically and quickly every time the door is opened. This can compensate for the lack of internal partitions and give you more flexibility in organizing storage.
Chest freezers
Chest freezers are more difficult to organize because you have to stack items on top of each other. To access the items at the bottom, you have to remove something from the top.
An advantage of chest freezers is that they can store larger containers than an upright. Chest freezers are best for long-term or bulk storage of materials.
Temperature control is much easier with a chest freezer because you open the door from the top and the cold air tends to stay in the chest instead of escaping.
Fridge/freezer combination
If you need a fridge and a freezer, instead of taking up space for two separate units, you can buy a combination unit that includes a separate freezer and fridge. They have separate doors for each function along with separate temperature controls and can be equipped with separate alarms and sensors. They may be just the thing for labs that are tight on space.
There are other considerations when choosing a laboratory refrigerator.
MAGNITUDE
How big should your fridge be? Only you can answer that question, but it’s an important one.
How much space should you dedicate to the refrigerator? You may want a large chest freezer, but if you don’t have the space, then it won’t solve your problem. Keep in mind that standing poles also allow you to store more material in a smaller footprint.
Are you storing large containers for long periods? Then a large chest freezer may be the answer.
Is the organization of materials very important to reduce laboratory errors? A straight one would be the right choice.
Need frequent access to refrigerated items? You should probably choose a small or under-counter model that you can place next to your workstation.
An analysis of your situation may reveal that you need more than one refrigerator to meet your requirements.
Location. Location. Location.
If you are planning to move your new freezer to a new location, you should be aware of the needs of the freezer. First, freezers don’t work as well in warm rooms. This makes their compressors work harder and reduces their useful life.
Also, freezers work best with space on all sides to improve air circulation Businessacademy1. Placing them on the wall or near other equipment can cause them to overheat and fail.
Finally, freezers create their own heat, which increases the temperature of the room, making the compressor work harder. Be careful not to place multiple freezers in the same area to avoid raising the room temperature too much for all freezers to work efficiently.
Temperature control
Many laboratory materials or specimens must be kept at precise temperatures to ensure their stability. With that in mind, if you need that level of control, be sure to choose a model with precise temperature control.
Many newer models have microprocessor-controlled thermostats that are much more accurate than older manual, dial-type, or analog units and even allow temperature settings accurate to one decimal place.
ALERTS
No matter how reliable or high quality your freezer is, the possibility of unpredictable, catastrophic failure is always a possibility. With that in mind, if you store valuable materials that you can’t afford to lose, a built-in alarm system is a must. Some systems can provide remote alerts, even notifying you via email, text, phone or pager, in addition to sounding an audible alarm when temperatures rise above limits.
Temperature sensors
Some disciplines, such as medicine, biology and food and drugs for example, require careful documentation of temperature for validation. There are sensors that collect data that can be used to validate material and air temperature as needed. Data can be stored for local or remote recovery as needed.
Manual melting
Manual defrost units are subject to ice build-up on the interior walls, which must be removed periodically. This means that the materials in the freezer will have to be removed and provided with alternative temporary storage during the process. You will also need to allow time for the freezer to cool enough to return the materials to the refrigerator.
Automatic melting
Many auto-defrost laboratory freezers use heat to melt the condenser coils, which, when in operation, will cause the temperature inside the freezer to rise. Circulating heat plus air removes any ice on the walls of the unit, but can endanger the materials inside the freezer if this situation is not part of your planning.
Often, just keeping the unit full is enough to prevent a substantial temperature change, however ice packs can be used to help. Mainly, you just need to be aware of the effect of the auto defrost cycle on the contents of the freezer.
Newer units have the ability to shorten defrost cycles and can be configured to shorten the cycle when temperatures rise above a certain temperature. Shorter automatic defrost cycles reduce risk to laboratory materials.
Automatic defrost units use more energy efficiently than their manual defrost counterparts.
Safety
In your industry, you can search for everything from freezer door locks to a record of when the freezer door was opened and who opened it. You can find basic locking doors on many refrigerator models, but for more elaborate systems you’ll need to choose more expensive or even custom models.
Visibility of the material
Inventory management or physical security can be as simple as being able to see what’s available. In the case of a refrigerator, it can be as simple as an insulated glass door. Basic upright freezers come with solid doors often with storage shelves or bins in the door. Models with insulated glass doors are more expensive and do not have additional space in the door.
Reversibility of upright freezer doors
It is now common for upright single-door lab freezers to have reversible doors to increase the flexibility of freezer placement in your lab. If this is a feature you need, be sure and confirm that the freezer you are considering has a hinged door.
Construction Material
Freezers come with coated or stainless steel interiors and exteriors. Stainless steel is resistant to stains and rust while painted steel surfaces when scratched can be at risk of corrosion. More than just aesthetics, stainless steel is a more durable material that can make cleaning the freezer easier and extend the life of your freezer.
Safety
Any unprotected electrical equipment can be a safety hazard in the wrong environment. Loose wires, short circuits, and burning lights can cause sparks which, in the presence of an oxygen-rich environment or flammable chemicals, can cause a fire or explosion. If this is a concern, units are available that are designed to withstand explosion.
I sincerely hope that this article has provided you with valuable information that helps you choose the best laboratory refrigerator for your needs.