Drager BG4 Statements of Fact 2 Questions taken from 2017 Drager BG4 Statements of Fact Progress Indicator: Question 6 of 15 6.  A typical oxygen-delivery system includes a ________, a regulator, and a delivery device.  Occasionally a humidifier will be added to provide moisture to the oxygen if the patient will be on the system for an extended time: Choices: Pressure regulator humidifier Pulse oximeter Oxygen source