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 NICU 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 (L10), 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, L10, and Lmax.

RESULTS

The overall average hourly Leq (M = 60.44 dB, range = 55-68 dB), L10 (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, L10 <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.