Choosing the right type of refrigerator for a cold chain is a critical factor in ensuring the successful flow of a cold chain. Before procuring a refrigerator, its capacity for precise temperature control and monitoring, alert systems, and secure insulation must be considered. A wide range of refrigerators is available in the market. However, not every unit can store sensitive materials like vaccines or biological samples. Investing in the right refrigerator for a cold chain would prove to be cost-effective in the long run through proper preservation of products and materials, ensuring a safe, organized inventory, and easing the work process for your employees.

All medical-grade refrigerators are manufactured to meet meticulous standards. A house or dorm-style refrigerator is not advisable for pharmaceutical storage. This is because it exposes items to possible temperature inconsistencies.

The main difference between medical and household refrigerators is the freezer. Using a dorm-style or bar-style freezer has a tendency to easily freeze vaccines or medical samples. The Centers for Disease Control and Prevention (CDC) discourages the use of combination refrigerator-freezers for laboratory storage and vaccines due to evident temperature irregularities.

Difference Between Dorm Style and Medical-Grade Refrigerators

Dormitory-Style Refrigerators

Dormitory-style refrigerators are not designed to provide a conducive stable temperature environment. These units experienced temperature excursions as high as 5℃ from the midpoint in studies conducted by the CDC. The fluctuations are due to the units’ design. Designed to only has one exterior door and an evaporator coil situated in the freezer compartment where cold air passes down into the main compartment. This type of setup causes inconsistent refrigerator temperatures.

Generally, dorm-style refrigerators do not have a temperature probe linked to digital data loggers. Due to this, many consumers purchase after-market equipment and install them on their own. They often run the wire used for the temperature probe through the front door. This method increases the likelihood of warm air from the outside flowing inside the refrigerator due to the lack of proper sealing. Most after-market probes are not intended for this use. They are designed to remain inside the fridge. Medical refrigerators use temperature probes with glycol-filled bottles to better reflect not only the temperature of the unit but also the actual temperature of the items stored within.

Due to the traditional nature of a standard fridge, the staff may also be tempted to use It for personal storage. Since communal refrigerators are constantly opened, they are more likely to experience temperature excursions throughout the day. These units are infrequently manufactured with strong temperature recovery. This might damage the sensitive materials stored inside. Medical refrigerators dissuade unwanted usage since the unit’s external appearance may intimidate employees from placing personal items. Many also have locks that regulate access and stickers to clearly mark the equipment for its intended use to prevent a mix-up.

Dormitory-Style Refrigerators
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Medical Refrigerators

All vaccines should be stored in refrigerator units or freezers that are specifically designed for biological storage. Medical refrigerators are stand-alone units that are intended for this usage. They experience fewer door openings since they cannot store food or personal items, unlike in communal fridges.

Medical refrigerators have a fixed temperature range. One powerful fan is installed within the unit for better air circulation and uniform temperature. Most medical units often have wire or perforated steel shelving. These materials promote better ventilation and airflow instead of solid glass shelves, often used in residential refrigerators.

Medical grade refrigerator for cold chain
Photo credit: www.euractiv.com

The units feature a temperature control panel with a digital thermostat. This allows quicker and more accurate temperature adjustment. Alarms are also installed, which notifies staff whenever the temperature falls out of the specified range. In order to prevent temperature leaks, medical refrigerators should use thermometers connected to glycol-encased probes via an internal connection.

Accucold Experiment

Accucold conducted an experiment to demonstrate that medical refrigerators have the capacity to maintain a more uniform temperature profile as opposed to residential use units. A dormitory-style refrigerator (SUMMIT CM406W) was tested against a medical-grade refrigerator (Accucold FF511LBIVAC. S). The refrigerator unit had a freezer and fridge compartment. The medical-grade unit was all-refrigerator. Glycol-encased probes linked to digital data loggers were used to accurately measure the temperature of the items inside the units. 

Study Comparing the Differences Between Dorm-Style & Medical Refrigerators for cold chain
Photo Credit: www.accucold.com

When comparing the temperature range data recorded from the dorm-style SUMMIT CM406W refrigerator and medical-grade Accucold FF511LBIVAC refrigerator, it is evident that the ranges of the dorm-style refrigerator, 4, 4, 6, & 8℉, are considerably larger than the ranges of the medical refrigerator, which are only 2, 1, 1, & 2℉. The standard deviations of the dorm-style refrigerator probes are also higher than those of the medical ones. It shows evidence of greater temperature fluctuations inside the dorm-style unit. 

On the other hand, the medical refrigerator exemplifies outstanding consistency in maintaining the specified temperature range. This consistency allows it to be more suitable for temperature-sensitive pharmaceutical materials, such as vaccines and biological samples.

 Dorm-style refrigerators are more affordable compared to medical refrigerators. However, using it in a pharmaceutical setup may pose a greater financial risk in the long run. This is due to the possible damages incurred by spoiled vaccines and samples. These units are acceptable for basic home storage of items, but they are highly discouraged from being used in medical laboratories.

Factors To Consider When Choosing A Refrigerator

Kind Of Material To Be Stored

When procuring a pharmaceutical refrigerator, one must consider the kind of material that will be stored in the units. Several refrigerators are designed to house specific materials. When storing plasma, blood, vaccines, or pharmaceutical supplies, the refrigerator unit should be suitable to the needs of the particular product to be stored. If the facility works with flammable materials, a fireproof refrigerator or freezer without ignition should be used.

Temperature Range

Various materials also have different temperature requirements. There are various kinds of cold storage units available with varied temperature capacities to suit multiple items. Standard pharmaceutical-grade refrigerators have a range of 2°C to 8°C (36°F to 46°F). Lab freezers have –10°C to –25°C (14°F to –13°F). Low-temperature freezers can store items at –45°C ( –49°F) while ultra-low freezers run from –50°C to –86°C (–58 °F to –123°F).

Storage Space

Internal space and external dimensions are also important deciding factors in choosing a refrigerator for a cold chain. The interior space should contain enough room to simultaneously fit all temperature-sensitive materials. Its external dimensions should also fit inside the facility. There are units of different sizes available to cater to the needs of various cold chain facilities. 

For a small facility with minimal inventory, a shorter under-counter or benchtop unit would suffice. For bigger facilities, there are two- and three-door refrigerator units available in the market that can fit a more extensive inventory. It is essential for materials to have adequate space inside. An overfilled refrigerator for a cold chain can cause accidents and damage items. However, too much-unneeded space can cost additional money and energy that can easily be avoided through proper initial planning.

Lab Layout

The particular location where the unit will be placed inside the labs should also be considered. The units have special ventilation requirements. A freestanding unit will need space at the top and at the sides of the unit to allow airflow. Clearance requirements must be checked as well. The unit may also require room behind, beside, or above it for the coils and other components to be connected safely.

Refrigerator Setup

Some units provide greater organization and accessibility to the staff compared to others. The unit’s materials also play a factor in how the crew will work in and around the fridge. Shelving, for example, can be made of different materials. Each material has a different effect on the unit. Glass shelves allow for easier cleaning of the unit, but it tends to disrupt air circulation inside the refrigerator for a cold chain. Wire, perforated, or plastic shelves allow better airflow in the unit, which will, in turn, help in keeping the materials at a consistent temperature. The installation of door storage can provide additional space for the materials. However, it is important to keep in mind that the items stored in this area would be more likely to be exposed to outside air every time the unit is opened.

Security Measures

In the case of unwanted incidents such as power outages or accidental tampering/ exposure, the unit should contain security measures and temperature regulation capacities. Self-closing doors, locks, and a rapid cool-down setting are some of the technologies that can be installed in the refrigerator unit. These technologies allow the unit to return to its proper temperature every time the door is opened or closed. Many units also have alarms that alert cold chain staff regarding temperature excursions. External temperature monitors can also be beneficial to properly observe the materials. This can be done without necessarily opening the door and disrupting the atmosphere within the unit. Emergency backup power options are also crucial in order to ensure the quality of time- and temperature-sensitive materials in the case of a power outage or other emergencies.

References:

https://k2sci.com/news/what-to-consider-when-buying-a-laboratory-refrigerator/https://www.accucold.com/medicalvsdormhttps://k2sci.com/news/what-to-know-when-choosing-a-medical-refrigerator/


1 Comment

Sub Zero Refrigerator Service Repair in Illinois · February 23, 2022 at 7:12 pm

Low Cost Appliance Repair is factory trained and authorized to service the full product line of Sub-Zero appliances.

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