What is the maximum runtime and room coverage for this humidifier?

The humidifier has a runtime of up to 70 hours, based on the lowest mist level setting. The room coverage is 426 ft² / 39.5 m², based on AHAM HU-1-2016 measurement as shown by independent laboratory testing. Actual runtime may vary depending on the natural humidity level, water temperature, and mist-level setting used. (Page 11)