Sound system equipment. Headphones and earphones associated with portable audio equipment. Maximum sound pressure level measurement methodology and limit considerations

The environmental noise level measurement in Dharan and Inaruwa cities of eastern Nepal were conducted and compared with the ambient noise standards provided by Government of Nepal. The noise pollution assessment was performed in autumn and winter seasons by the indicator average day time sound pressure level (Ld, during 7.00 to 22.00 hrs) and average night time sound pressure level (Ln, during 22.00 to 7.00 hrs). The Ld and Ln values at the commercial, silence and residential zones of Dharan were 78 to 82 and 72 to 73, 65 to 73 and 60 to 70, 65 to 76 and 62 to 64 dB(A) in autumn and 78 to 79 and 72 to 76, 64 to 71 and 58 to 68, 63 to 74 and 60 to 62 dB(A) in winter, respectively whereas for Inaruwa, measurement were 75 to 77 and 73 to 75, 59 and 57, 67 and 60 dB(A) in autumn and 66 to 70 and 63 to 68, 55 and 53, 65 and 58 dB(A) in winter, respectively. The results showed that noise levels exceeded the standard value at most of the sites.

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The Cry Characteristics of an Infant Who Died of the Sudden Infant Death Syndrome

Journal of Speech and Hearing Disorders ◽

10.1044/jshd.4604.359 ◽

1981 ◽

Vol 46 (4) ◽

pp. 359-363 ◽

Cited By ~ 30

Author(s):

R. H. Colton ◽

A. Steinschneider

Keyword(s):

Sudden Infant Death Syndrome ◽

Sound Pressure Level ◽

Infant Death ◽

Sound Pressure ◽

Sudden Infant Death ◽

Pressure Level ◽

Sudden Infant ◽

Term Infants ◽

Formant Frequencies ◽

Level Measurement

Fourteen cries of a four day old infant who subsequently died suddenly of unexplained causes were analyzed on nine acoustic characteristics including f o , duration, formant frequencies and sound pressure level. In comparison to a group of newborn controls, the Sudden Infant Death Syndrome (SIDS) victim's cries exhibited a lower f o , longer duration, lower formant frequencies and greater sound pressure level throughout the spectrum. Cry duration and sound pressure levels, however, deviated in excess of one standard deviation from the mean of the other newborns. Similar findings resulted when the SIDS infant was compared to a group of full term infants who were siblings of SIDS victims, although the magnitude of the differences was slightly less especially with respect to sound pressure level. Measurement of selected acoustic variables in a newborn's cry may be of value in our understanding of SIDS and for identifying infants at risks.

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