Comparison of individual alarm sounds in International Electrotechnical Commission (IEC) standard and icon sets. The overall accuracy rates shown do not account for the nested data structure (fig. 1) and are, therefore, averaged across subjects and sessions. Card = cardiovascular; Drug = drug administration; Gen = general; Oxy = oxygenation; Perf = artificial perfusion; Pow = equipment failure; Temp = temperature; Vent = ventilation.