RuuviTag sensors are recommended to be used within -20°C to +65°C. Maximum operating temperature for electronics and enclosure must stay within -40°C to +85°C temperature range.
The standard battery shipped with the device works from -20°C to +65°C.
RuuviTag has to be used with the included waterproof enclosure to prevent water or any other conductive element from getting in contact with the sensitive electronic components.
Important notice: do not place the RuuviTag in direct contact with water.