Unit provides more features than any other single gas monitor available. Interchangeable smart sensors enable this unit to be quickly adapted to monitor unsafe levels of oxygen or a variety of toxic gases. Intuitive four-button navigation allows easy access to setup, operation and calibration functions. Monitor communicates directly via an infrared interface to optional accessories like the DS2 Docking Station to further simplify and automate calibration, bump testing and data downloading. Standard STEL and TWA readings and datalogging of up to one year of survey data are featured along with an event-logger that records the past 15 alarm events. A protective concussion-proof overmold protects the unit from abuse in harsh industrial environments.