Figure 3From: The influence of APACHE II score on the average noise level in an intensive care unit: an observational studyAverage noise levels in the first four days. Means and 95-% confidence intervals are shown for L Aeq averaged over 22 patients. Daytime was defined to be between 7 am and 9 pm (therefore, LAeq,14h for daytime, LAeq,10h for nighttime).Back to article page