Figure 4From: Methods for evaluation of helium/oxygen delivery through non-rebreather facemasksAverage inhaled helium concentrations for the Hi-Ox mask are displayed for a range of supply flow rates of helium/oxygen (He/O 2 ) 78/22. For the clinical data [17], error bars represent the limits of the range of values measured for six healthy, adult subjects. For all other columns, data was obtained from bench measurements made using the thermal conductivity analyzer. Error bars represent the ±2% accuracy of the analyzer.Back to article page