FIELD: medicine.
SUBSTANCE: invention relates to bordering areas of science, technology and manufacturing, namely to hearing physiology and otolaryngology, human hygiene, ecology of noise plants, sound dosimetry and metrology of sound parametres. Total number Z of auditory receptors -exterior and interior Corti's cochlear hair cells (CC), able at standard sound frequency fs = 1000 Hz to create sensation of tones with loudness E, daphone = L, bel, corresponding to sound pressure p(L) at level L at hearing threshold po = 2·10-5Pa, Z = Ne + Ni where Ne = 15 exterior CC and Ni = 1interior CC. Determined are connection between level L of sound pressure p(L) and number n of functioning exterior CC reacting on sound pressure of said level: L = n - 1, and connections of these values with sound pressure in internal ear g(L, n) = g(L), and dose of sound impact D(L) = g(L)2τ during time τ, which do not cause destruction of exterior CC. For hearing analyser determined is maximal number ns of exterior CC located in exterior row of cochlear duct and responsible for perception of sound pressure with level Ls, at which they are able tolerantly, without destruction, to function permanently and without adaptation: ns = 6 of exterior CC, and level of sound pressure: Ls = 5 B, which corresponds to sound loudness Es = 5 daphone = 50 phone. Reference points in hearing physiology for ns = 6 of exterior CC and sound pressure level Ls = 5 B = 50 dB are calculated: for maximal sound pressure in internal ear g(Ls, ns) = 2.156·10-4 Pa, for maximal dose of sound impact in internal ear with impact duration T = 360 years, on which work of ear is intended, D(Ls) = 0.147 Pa2hour.
EFFECT: method allows to determine maximal permissible parametres of sound impact on people in sound field 1000 Hz taking into account physiological, bio- and psychophysical foundation.
3 cl, 12 dwg
Authors
Dates
2009-10-10—Published
2008-03-20—Filed