HCL Gas Detector Honeywell is a state-of-the-art business solution designed to detect and alarm toxic gas concentrations in the workplace. Using advanced sensors, it detects minute levels of hydrogen chloride present in indoor or outdoor air and releases a warning before any dangerous level is reached. With its easy-to-use design and optional features such as audible alarms and remote monitoring, Honeywell Gas Detector ensures that your staff, customers, and property are always protected from potential health hazards and other damage, no matter where you’re doing business.