Thermal Efficiency: The Benefits of Curtains in the Cold Room and Freezer

The debate regarding the benefits of using curtains for cold rooms and freezer rooms remains surprisingly active despite the clear technological advantages available today. There are significant benefits for using curtains in the cold room and freezer environments, yet many commercial kitchens still fail to recognise how air or plastic curtains save on energy costs, reduce maintenance, and maintain proper temperatures.

2.0 The Physics of Thermal Exchange

We understand that each time a cold room door is opened, the heavy cold air is effectively sucked out, creating a vacuum that warm, moist air quickly fills. The temperature differential between an ambient kitchen and a cold room is virtually the same as the difference between a freezer room and a cold room.

Consider an ambient kitchen temperature of 24°C compared to a fridge temperature of 4°C, or a freezer at -18°C compared to a cold room at 4°C. In both instances, there is a 20°C to 22°C difference in temperature. Without a barrier, this exchange happens instantly, forcing the refrigeration plant to work significantly harder to recover.

3.0 Temperature Benefits and Food Safety

Uncontrolled air exchange leads to condensation, ice build-up, and energy loss. By creating a barrier that limits this exchange, less energy is required to maintain the set point. More importantly, the air temperature remains constant, which significantly extends the shelf life of the products stored within.

From a microbiological perspective, reduced moisture due to lowered condensation means less opportunity for bacteria to thrive. Pathogens like Listeria monocytogenes prefer damp, chilled environments; by keeping the cold room dry and stable, you mitigate this risk. Furthermore, the ice build-up resulting from temperature exchange is a major health and safety hazard, creating slippery floors that lead to workplace injuries.

4.0 Energy, Maintenance, and Operational Logic

While there is an initial cost to the purchase of air or plastic curtains, the long-term benefits are undeniable. The two major cost benefits involve energy usage and mechanical strain. Continuous cooling of units due to air loss can cause electricity costs to skyrocket.

The second benefit involves the condensers. By reducing the frequency of the cooling cycle, there is less strain on the mechanical components. This saves on the maintenance and replacement of expensive units, including electrical elements like internal lighting which can fail prematurely due to constant moisture exposure.

5.0 Air Curtains versus Physical Strip Curtains

Air curtains offer clear advantages regarding visibility and workflow. Because there is no physical barrier, staff have a clear line of sight, reducing the risk of collisions. There is also zero risk of physical cross-contamination, as nothing touches the food containers or the staff members passing through.

In contrast, physical PVC curtains provide a more solid thermal barrier. They are generally less costly to install and do not require electricity to operate. However, if they are not kept clean, they carry a high risk of cross-contamination as they brush against every person and tray entering the room.

6.0 Realities and Maintenance Challenges

Deciding which type of curtain to use is not a simple choice, as both systems have operational difficulties that must be managed.

• Air curtains require regular electrical maintenance and can become a breeding ground for moulds if the internal fans and housings are not cleaned.
• If the air pressure is incorrectly calibrated, air curtains can be ineffective, allowing cold air to escape from the bottom of the doorway.
• Physical curtains are often moved aside or tied back by staff who find them a nuisance, which completely defeats their purpose.
• PVC strips can collect dust, grease, and food spillages, requiring a dedicated cleaning schedule to remain hygienic.

7.0 HFS Best Practice Protocols

To overcome these difficulties, training and awareness are essential. At Hygiene Food Safety, we recommend the following protocols for your refrigeration barriers:

For Air Curtains:

• Units must be cleaned internally as required to prevent the accumulation of dust and organic matter.
• Regular professional maintenance is required to ensure proper airflow and motor health.
• Units should be automated to trigger upon the door opening to ensure they are never accidentally left off.

For Physical Curtains:

• Strips must be cleaned and sanitised weekly as part of the deep cleaning schedule.
• Any damaged or clouded strips should be replaced immediately to maintain visibility and safety.
• Staff must be trained to walk through the centre of the strips rather than pulling them to the side and hooking them over the door frame.

In conclusion, the combination of energy savings, mechanical longevity, and improved food safety makes the installation of curtains an essential component of any modern kitchen. By managing the temperature exchange, you protect both your profits and your customers.

Is your refrigeration equipment running at peak performance? Check our Food Safety Checklists for temperature logs or read our guide on Temperature Control in the Kitchen to learn more about safe storage thresholds.