The Importance of Noise Attenuation Levels in Neonatal Incubators

Abstract Background: It is known that high noise levels can be harmful to the preterm infant, causing physiological and psychological disorders. It is also known that premature babies spend a lot of time in an incubator. In this sense, many studies show that incubator noise levels can range from 45 dB to 70 dB. However, these differences in noise levels depend, fundamentally, on the methodology used, which a very varied. The aim of this study is to know the levels of noise from fan in the incubator itself and how much it is able to isolate the noises coming from the outside. Methods: It were characterized the acoustic behavior of several models of incubators. For this purpose it was measured the incubators noise level within an anechoic chamber. It was also used a 4224 pink noise generating source to determine the isolation levels of the incubators and one microphones inside the incubator and another one outside connect to a SVAN958 noise analyzer. Results: The incubators produced continuous equivalent noise levels of between 53.5 dB and 58 dB. The analysis of isolation showed that the level varied from one incubator to another, between 5.2 dB and 10.4 dB. In addition, the isolation level in one-third octave bands varied from one incubator model to another. Conclusions: Preterm infants in an incubator are exposed to noise levels very far from the international recommendations, even if the incubators are meeting the noise criteria set out in the IEC60601-2-19: 2009 standard of 60 dBA under normal use conditions.