GB/T 32209-2015 "Multi-component harmful gas detection and alarm devices" specifies the technical requirements, test methods, inspection rules, and other aspects for multi-component harmful gas detection and alarm devices. It applies to alarm products capable of simultaneously detecting multiple harmful gases. The instruments detect gas concentrations based on corresponding sensing principles and are equipped with functions such as alarm, display, and data output. They must undergo performance tests including zero drift, span drift, and response time. Testing requires equipment such as standard gases, gas dilution devices, and precision timers to ensure the accuracy and reliability of the alarms in industrial environments and other scenarios.