Elevated Sound Levels within a Busy NICU

Purpose: Elevated sound levels in the NICU may contribute to undesirable physiologic and behavioral effects in preterm infants. This study describes sound levels in a busy NICU in the southeastern U.S. and compares the findings with recommended NICE noise level standards. Design: NICU sound levels were recorded continuously at nine different locations within the NICU. Hourly measurements of loudness equivalent (Leq) sound level, sound level exceeded 10 percent of the time (L-10), and maximum sound level (Lmax) were determined. Sample: Sound levels were sampled from nine different locations within the NICU. Main Outcome Variable: Sound levels are described using the hourly, A-weighted Leq, L-10, and Lmax. Results: The overall average hourly Leq (M = 60.44 dB, range = 55-68 dB), L-10 (M = 59.26 dB, range = 55-66 dB), and Lmax (M = 78.39, range = 69-93 dB) were often above the recommended sound levels (hourly Leq <50 dB, L-10 <55 dB, and 1-second Lmax <70 dB). In addition, certain times of day, such as 6-7 AM and 10 AM-12 noon, were noisier than other times of day.