Wireless differential pressure loggers are used to measure pressure difference between rooms in hospitals or in production facilities. Loggers work with three applications (Efento Inspector, Efento Logger, Efento Cloud) and allow users to measure and register pressure difference between rooms, notify users with SMS / e-mails when a safa threshold has been exceeded and generate automatic reports. The battery ensures maintenance-free operation for at least two years. The sensors communicate wirelessly with smartphones or Efento Gateway in Bluetooth Low Energy technology.The maximum range is approx. 100 m in line of sight. Temperature sensors have built-in memory which stores 28 000 measurements. Loggers are equipped with two 1 m long probes