As Japan braces for a cold snap, smartphone users are being urged to protect their devices from condensation, which can cause irreparable damage.

Japanese weather officials are warning of severe cold and heavy snow nationwide through Wednesday.

A mobile phone repair shop in Tokyo says requests for repairs increase in winter because of condensation, which occurs due to rapid changes in temperature.

An example is when a smartphone is recharged as soon as the user gets home or after being left near a window or other cold place.

Some users hang their smartphones across their body rather than carrying them in their bags or pockets.

This exposes the smartphones to the cold, sometimes causing them to malfunction as soon as the user enters a warm room.

When condensation occurs, impurities in the water erode the metal parts inside the smartphone. This can result in data loss.

The repair shop says users should put their smartphones in their bags or pockets to avoid exposure to excessive cold.

It warns that exposing a cold smartphone to heat from a hair dryer or placing it near a heater to warm it can also result in condensation.