TABLE 4.

Complicated Specifications of Ventilators

Issues	Cause for Specifications Not Being User-Friendly
Intuitiveness of the design when users encounter some trouble	The device has no display, or display message not easy to understand when users encounter some trouble
	The device does not start working just by pressing the start button (concluded as standby mode)
	Two accessories can be connected for different purposes
Robustness of design: alarms and accessories cannot be easily removed	Monitoring equipment (e.g., SPO2 monitor) or the ventilator’s accessories were easily removed with external force
The alarm continues to sound when a device has an issue	The trouble was not resolved, but the alarm bell stopped ringing, or the monitor screen notified the trouble
Automatic calculation system when the ventilator is connected to mobile oxygen gas	The user needs to calculate how much oxygen can be kept from the remaining gas amount and the gas flow rate of the oxygen cylinder