GB/T 7341.5-2018Electroacoustics -- Audiometric equipment -- Part 5: Instruments for the measurement of aural acoustic impedance/admittance (English PDF)

Foreword

GB/T 7341 "Electrical Acoustic Audiometry Equipment" is divided into the following parts.

--- Part 1. Pure tone audiometer;

--- Part 2. Language audiometry equipment;

--- Part 3. Short continuous auditory test signals for audiometry and neurology;

--- Part 4. Extending high-frequency audiometry equipment;

---Part 5. Measuring instruments for otoacoustic impedance/admittance;

--- Part 6. Measuring instruments for otoacoustic emissions;

--- Part 7. Measuring instruments for auditory brainstem response.

This part is the fifth part of GB/T 7341.

This part is drafted in accordance with the rules given in GB/T 1.1-2009.

This part replaces GB/T 15953-1995 "Earing Impedance/Admittance Measuring Instrument". Compared with GB/T 15953-1995, mainly

The technical content changes as follows.

--- Modify the "probe buckle" to "ear plug" (see 3.13 and.1995 version 3.13);

--- Revised the contents of Chapter 4 and listed it as Chapter 10 (see Chapter 10 and Chapter 4 of the.1995 edition);

--- Revised the contents of Chapter 5, and modified 5.1 into Chapter 4 (see Chapter 4 and Chapter 5 of the.1995 edition);

--- Revised the contents of Chapter 6, and revised 6.1.2 to Appendix C (see Appendix C and Chapter 6 of the.1995 edition);

--- Increased measurement expansion uncertainty and maximum allowable value content (see 6.6);

--- Added an overview of Chapter 7 (see 7.1);

--- Modified the contents of 8.3 (see 8.3 and.1995 edition 8.3).

This part uses the translation method equivalent to IEC 60645-5.2004 "Electrical Acoustic Audiometry Equipment Part 5. Otoacoustic Impedance/Admittance

measuring instrument".

The documents of our country that have a consistent correspondence with the international documents referenced in this part are as follows.

GB -9706.1-2007 Medical electrical equipment - Part 1. General requirements for safety (IEC 60601-1.1988 A1.1991

A2..1995, IDT)

Introduction

In the field of audiometry and diagnostics, a series of specially designed instruments are used with their sound detection signals with different frequency and time characteristics.

No. to evaluate the acoustic impedance/admittance of the human ear. The practical application of such instruments is largely related to the measurement of otoacoustic impedance/admittance changes.

Otoacoustic impedance/admittance changes are caused by changes in the air pressure of the external auditory canal or by excitation of the middle ear muscles.

Electroacoustic audiometry equipment

Part 5. Measuring instruments for otoacoustic impedance/admittance

1 Scope

This part of GB/T 7341 specifies the performance of three types of otoacoustic impedance/admittance measuring instruments and the facilities provided for these instruments.

Conditions, and test methods used for acceptance testing and to guide routine calibration.

This section applies to instruments that measure the acoustic impedance/admittance in the external auditory canal using the specified pure tone detection signal. It is also suitable for other explorations.

This type of instrument for measuring signals.

This section is intended to ensure consistency with all types of instruments in this section under comparable test conditions. This section is not intended to constrain new features

The development or introduction does not hinder the innovation of technical methods.

2 Normative references

The following documents are indispensable for the application of this document. For dated references, only dated versions apply to this article.

Pieces. For undated references, the latest edition (including all amendments) applies to this document.

GB/T 7341.1-2010 Electroacoustic audiometry equipment - Part 1. Pure tone audiometer (IEC 60645-1.2001, IDT)

IEC 60126 IEC reference coupler for measuring hearing aids using earphones that are plugged in with the human ear (IEC reference)

Couplerforthemeasurementofhearingaidsusingearphonescoupledtotheearbymeansofearin-

Serts)1)

IEC 60601-1 Medical electronic devices - Part 1. General safety requirements (Medicalelectricalequipment-Part 1.

Generalrequirementsforsafety)

IEC 60601-1-2 Medical electronic devices - Part 1-2. General safety requirements Secondary standard. Electromagnetic compatibility requirements and testing

(Medicalelectricalequipment-Part 1-2. Generalrequirementsforsafety-Colateralstandard.Elec-

tromagneticcompatibility-Requirementsandtests)

IEC 60601-1-4 Medical electronic devices - Part 1-4. General safety requirements

(Medicalelectricalequipment-Part 1-4. Generalrequirementsforsafety-Colateralstandard.Pro-

Grammableelectricalmedicalsystems)

BIPM/IEC /IFCC/ISO /IUPAC/IUPAP/OIML Guidance for the Expression of Measurement Uncertainty [Guidetothe

Expressionofuncertaintyinmeasurement(GUM)].

1) The subsequent revision will be IEC 60318-5.

3 Terms and definitions

The following terms and definitions apply to this document.

Note. The units in this section are consistent with the International System of Units (SI) units, but the audiology test results are often used to other units in order to convert them.

Into the International System of Units (SI) unit, special preparation of Appendix B.

3.1

Ear impedance/admittance auralimpedance/admittance

A generic term covering all aspects of otoacoustic impedance/admittance.

Note. In addition to the special provisions of the document, this part uses ear impedance/admittance as a general term, which covers all aspects of otoacoustic impedance/admittance.

3.2

Acoustic impedance acousticimpedance

The ratio of the sound pressure to the volumetric velocity through the surface at a defined surface.

Note 1. The symbol is Za, and the unit is Pas per cubic meter (Pa.s/m3).

Note 2. The amount usually measured is the modulus.

3.3

Acoustic resistance

The real component of the complex acoustic impedance.

Note. The symbol is Ra, and the unit is Pas per cubic meter (Pa.s/m3).

3.4

Acoustic resistance

The imaginary component of the complex acoustic impedance.

Note. The symbol is Xa and the unit is Pas per cubic meter (Pa.s/m3).

3.5

Acoustic admittance acousticadmittance

In a prescribed plane, the reciprocal of the acoustic impedance of the plane.

Note 1. The symbol is Ya, and the unit is cubic meters per pascal [m3/(Pa.s)].

Note 2. Acoustic admittance on a certain surface is the complex ratio of the volume velocity flowing through the surface to the sound pressure uniformly distributed on the surface. Usually, the measured amount is the modulus.

3.6

Acoustic conductance

The real component of the complex acoustic admittance.

Note. The symbol is Ga, and the unit is cubic meters per pascal [m3/(Pa.s)].

3.7

Sonar acousticususceptance

The imaginary component of the complex acoustic admittance.

Note. The symbol is Ba, and the unit is cubic meters per pascal [m3/(Pa.s)].

3.8

Acoustic quality

The ratio of the stimulating sound pressure to the rate of change of the resulting volumetric velocity.

Note. Sound quality is also called sonar. The symbol is Ma, and the unit is Pascal square second per cubic meter (Pa.s2/m3).

3.9

Acoustic compliancecompliance

The ratio of volume displacement to sound pressure.

Note. The symbol is Ca, and the unit is cubic meters per pen (m3/Pa).

3.10

Equivalent volume equivalentvolume

Provides the volume of a hard-walled cylindrical air cavity with equivalent acoustic impedance/admittance.

Note 1. This volume is expressed by the formula.

Ve=gamma.ps.Ca=rho.c2.Ca

In the formula.

Ve---equivalent volume in cubic meters (m3);

gamma --- air constant pressure specific heat ratio to constant heat (approx. 1.40);

Ps---atmospheric pressure, the unit is Pa (Pa);

rho --- the air density at the time of measurement and the atmospheric pressure, in kilograms per cubic meter (kg/m3);

c --- the speed of sound at the time of measurement and atmospheric pressure, in meters per second (m/s);

Ca---sounding, in cubic meters per kPa (m3/Pa).

Note 2. In practical applications, the ear impedance/admittance of the detected audio frequency of 226 Hz is taken as the equivalent volume of air.

Note 3. For a sound frequency of 226 Hz, as long as the physical volume does not exceed 5 cm3, the equivalent volume of air is equal to its physical volume.

3.11

Relative pressure in the external auditory canal relativepressureinexternalacousticmeatus

The difference between the pressure in the external auditory canal and the atmospheric pressure.

Note. The relative pressure unit is ten Pa (daPa).

3.12

Probe probe

A coupling device for insertion of the external auditory canal to connect the instrument to the human ear.

3.13

Earplug eartip

A device used to seal the probe from the external auditory canal.

3.14

Probe signal probesignal

An acoustic signal sent by the probe to the external auditory canal.

Note. This signal is used to measure acoustic impedance/admittance.

3.15

Probe ear probear

There are ears that are inserted into the probe.

3.16

Measuring plane measurementplane

The plane at the front surface of the probe perpendicular to the volumetric velocity vector.

3.17

Tympanometry

Measurement of acoustic impedance/admittance in the external auditory canal with air pressure.

Note. The measured acoustic impedance/admittance value will be related to the rate of change and direction of air pressure; also the time required to maintain a certain atmospheric pressure in the external auditory canal.

related.

3.17.1

Measurement plane tympanometry measurementplanetympanometry

The measurement of the ear impedance/admittance change in the measurement plane, including the impedance/admittance of the middle ear and part of the external ear canal combination.

3.17.2

Otometer compensation tympanometry measurement metus-compensatedtympanometry

For the specified suitable probe, the otoacoustic impedance/admittance obtained at the specified reference pressure and the test pressure in the external auditory canal

Measurement of the amount difference.

Note 1. The reference pressure should be effective in eliminating the influence of the middle ear.

Note 2. The reference pressure is usually.200daPa and the indicated pressure difference. It can also be set to.200daPa relative to the ambient pressure, which gives the maximum admittance or minimum.

Impedance indication.

3.18

Tympanogram

A graphical representation showing the magnitude of the impedance/admittance of the middle ear in the ear canal as a function of atmospheric pressure.

3.19

Middle ear muscle reflection middle-earmusclereflex

Changes in middle ear muscle tone when responding to stimuli.

Note. This change can be measured by changes in acoustic impedance/admittance in the external auditory canal.

3.19.1

Acoustic reflection

Middle ear muscle reflex induced by acoustic stimulation.

3.19.2

Non-acoustic reflex

Middle ear muscle reflex induced by non-stimulus.

3.20

Acoustic reflex stimuli acousticreflexactivatingstimulus

Acoustic stimuli used to induce acoustic reflection.

3.21

Stimulated ear stimulusear

An ear that is stimulated by acoustic reflection to induce reflection of the middle ear muscle.

3.22

Ipsilateral reflection ipsilateralreflex

Middle ear muscle reflex induced in the stimulated ear.

3.23

Contralateral reflection

Middle ear muscle reflex induced in the opposite ear of the stimulated ear.

4 Requirements for the specified type of instrument

The most basic mandatory functions specified for the three different types of otoacoustic impedance/admittance instruments are given in Table 1, and other functions are not excluded. This

The three types are related to the basic applications they envision.

Table 1 Mandatory functions of the ear impedance/admittance instrument

Types of

Diagnostic/clinical tympanometry/reflex screening tympanometry screening

Detection signal frequency 226Hz x x x

Ear impedance/admittance measurement system

Measuring plane tympanometry x a x a x a

Ear canal compensation tympanometry x a x a x a

Pneumatic system

Manual pressure change x

Automatic pressure change x x x

Acoustic reflex stimulation system

Contralateral stimulation x

Ipsilateral stimulation x x

Table 1 (continued)

Types of

Diagnostic/clinical tympanometry/reflex screening tympanometry screening

Sound stimulation.

Pure tone x x

Broadband noise x

Stimulus level control x

Result representation

Display or visual indicator x x x

Print output x

Data interface x

a Any of the two should be provided.

5 General technical specifications