Why can't cold storage doors be opened from the inside?

The one-way, externally-opening design of cold storage doors may seem to restrict escape, but it is actually a necessary measure to ensure the stability of the low-temperature environment and personnel safety, with its design logic closely linked to the core functions of cold storage.

In terms of thermal insulation needs, cold storage must maintain a low temperature below -18℃, and the door adopts a multi-layer polyurethane foam sealing structure with a thickness of 10-15cm. If designed for two-way opening, the sealing strips cannot fit completely, leading to a cold loss rate increase of over 30%, a sudden rise in compressor load, and an energy consumption increase of 25%-40%. The one-way external opening design, combined with magnetic sealing, can minimize cold leakage through gaps and ensure stable internal temperatures.

Structural safety is another key factor. Frost accumulation easily occurs inside cold storage due to low temperatures, and the ground and door handles may freeze and become slippery. The hinges and locks of externally-opening doors are installed outside, which can prevent low temperatures from rusting metal components and extend their service life by 3-5 years. If opened from the inside, the door lock mechanism would be exposed to a low-temperature, high-humidity environment, easily failing due to freezing and jamming, which would instead increase the risk of entrapment.

In terms of safety regulations, although cold storage doors cannot be directly pulled open from the inside, they are all equipped with emergency escape devices. National standards require that a push-rod emergency unlocking device must be installed inside the storage; applying a force of less than 50N can trigger a mechanical linkage mechanism, instantly releasing the locked state. Meanwhile, acoustic and optical alarm systems and emergency lighting must be installed inside, linked with the door unlocking device, to ensure that personnel can quickly locate escape routes in emergencies.

This design is also related to industry accident lessons. In the past, two-way opening cold storage units had cases where accidental door closure due to misoperation caused locks to freeze quickly at low temperatures, trapping people. The combination of one-way external opening and emergency unlocking not only prevents cold loss from unnecessary door openings but also ensures safety through standardized escape devices, and has now become a universal standard in global cold storage design.

Correctly understanding the design logic of cold storage doors and regularly inspecting emergency unlocking devices and alarm systems can ensure the efficient operation of cold storage while building a solid safety barrier for personnel.