Sound Level Exposure of High-Risk Infants in Different Environmental Conditions

Purposes: To provide descriptive information about the sound levels to which high-risk infants are exposed in various actual environmental conditions in the NICU, including the impact of physical renovation on sound levels, and to assess the contributions of various types of equipment, alarms, and activities to sound levels in simulated conditions in the NICU. Design: Descriptive and comparative design. Sample: Convenience sample of 134 infants at a southeastern quarternary children's hospital. Main Outcome Variable: A-weighted decibel (dBA) sound levels under various actual and simulated environmental conditions. Results: The renovated NICU was, on average, 4-6 dBA quieter across all environmental conditions than a comparable nonrenovated room, representing a significant sound level reduction. Sound levels remained above consensus recommendations despite physical redesign and staff training. Respiratory therapy equipment, alarms, staff talking, and infant fussiness contributed to higher sound levels. Conclusion: Evidence-based sound-reducing strategies are proposed. Findings were used to plan environment management as part of a developmental, family-centered care, performance improvement program and in new NICU planning.