Hospital Noise Research

A noise-sensor light alarm reduces noise in the newborn intensive care unit

Chang YJ, Pan YJ, Lin YJ, Chang YZ, Lin CH


Department of Nursing, College of Medicine, National Cheng Kung University, Taiwan, Republic of China.


This one-group pre-post test design was to evaluate sound distribution and sudden peak noise frequencies (SPNs) and the associated events after using a noise-sensor light alarm in a tertiary neonatal intensive care unit (NICU). The alarm is activated as the sound level reaches>or=65 A-weighted decibel (dBA). The environmental sound level was monitored continuously for a period of 1 week before and 1 month after using the alarm. The mean sound level in the incubator of patients receiving ventilator support before and after using the device were 58.0+/-0.6 and 56.4+/-0.7 dBA (t=8.619; p<0.001), whereas those at the radiant heated bed were 58.0+/-2.4 and 58.1+/-2.0 dBA (t=0.715; p=0.476). The percentage of observation time of sound levels<58 dBA increased by 28% in the incubator and 4% at the radiant heated bed (p<0.001). Episodes of SPN decreased from 630 to 185 times/d in the incubator and from 2069 to 748 times/d at the radiant heated bed after using the device. The noise-sensor light alarm effectively reduces sound level and episodes of SPN in the NICU. This may alleviate stress of noise for newborns with critical illness.