LoRaWAN hydrogen chloride (HCL) sensor is an IoT wireless sensor developed based on LoRa wireless technology, with built-in hydrogen chloride sensor and temperature and humidity sensors. It utilizes electrochemical principles to monitor the concentration, temperature, and humidity of hydrogen chloride in the environment in real-time. This system has the characteristics of high detection accuracy, stable performance, and low power consumption, and is widely used in environmental monitoring, industrial emission monitoring, chemical plants, and other fields.