BI-Level Machine Pessure adjustment range: level adjustable:4-20cm H2O level intervals: 0:5cmH2O, Tolerance:+0.5cmH2O. Time of pressure increasing:0-40min, Set of level intervals: 5min, Accurancy:+1 min. Humidifying temperature: Adjustable to the temperature of no more than 41oC. ventilating per minute no less than 20Lmin when working pressure is 10cmH2O. Alarm Power failure alarm Leakage alarm.