Every opening lets warm, humid air enter and cold air leave.

In short: prepare before opening, move a planned batch and close the door fully. Do not rely on an arbitrary ten-second rule.

Keep the route clear, use a closer or alarm where appropriate and repair a door that does not latch. In busy sites, strip curtains, an air curtain, a lobby or a high-speed door may reduce exposure.

Long openings also bring moisture that freezes on the evaporator and door frame. Record repeated alarms and fix the workflow or hardware causing them.

Why the door dominates

Every time the door opens, warm, humid room air rushes in and the refrigeration system has to pull that heat back out. In a busy operation this infiltration load dominates the energy bill — typically 30–50 % of total consumption — and a single careless habit, such as a door propped open during a delivery, can undo an otherwise efficient installation.

A door left open for 1 minute can take 5–10 minutes to recover temperature. During that recovery window the interior sits warmer than setpoint, which is exactly the condition food-safety rules are written to prevent.

Best practice

• Plan before you enter. Know what you need and gather several items in one trip rather than making repeated visits.
• Close the door fully, every time. Never prop it open "just for a second" — confirm the latch engages.
• Batch retrievals. Organise the working day so multiple items come out in single entries.
• Consider strip curtains on high-traffic doorways. Correctly fitted curtains can reduce warm-air exchange, but the effect depends on traffic, doorway size and use.
• Train everyone with access. The habit only works if every member of staff understands why it matters.

The 10-second rule: Aim to complete each entry in under 10 seconds. Where that is not realistic, fit a door alarm that sounds after ~30 seconds open — a cheap, effective prompt to close up.

Related articles

• Daily operation overview
• Product placement
• Temperature monitoring
• Loading new products
• Door types & specifications
• Energy efficiency

For help specifying strip curtains or door alarms for your room, contact [email protected].