AS/NZS 1270:1999

AS/NZS 1270:1999 ACOUSTICS-HEARING PROTECTORS

PREFACE

CONTENTS

SECTION 1 SCOPE AND GENERAL

1.1 SCOPE

1.2 APPLICATION

1.3 REFERENCED DOCUMENTS

1.4 DEFINITIONS

1.4.1 Acoustic helmet

1.4.2 Diffuse sound field

1.4.3 Disposable earplug

1.4.4 Ear canal cap

1.4.5 Earmuff

1.4.6 Earplug

1.4.7 Hearing protector

1.4.8 Occluded-ear threshold of hearing

1.4.9 Open-ear threshold of hearing

1.4.10 Pink noise

1.4.11 Real-ear attenuation

1.4.12 Reference point

1.4.13 Reverberation time

1.4.14 Suspension system

1.4.15 Test signal

1.4.16 Threshold of hearing

1.4.17 User formable earplug

SECTION 2 GENERAL REQUIREMENTS

2.1 DESIGN AND CONSTRUCTION

2.1.1 General

2.1.2 Earmuffs

2.2 MATERIALS

2.3 WEARER INFORMATION

2.3.1 Information in or on the packaging

2.3.2 Information on the packaging

2.3.3 Information with each packaged pair of earplugs

2.4 MARKING

SECTION 3 PERFORMANCE

3.1 PHYSICAL REQUIREMENTS

3.2 TEST PROCEDURES

3.2.1 General

3.2.2 Examination

3.2.3 Preparation

3.2.4 Clamping force test

3.2.5 Dry heat test

3.2.6 Low temperature drop test

3.2.7 Cleaning

3.2.8 Second measurement of clamping force

3.2.9 Attenuation

SECTION 4 METHOD FOR MEASUREMENT OF THE REAL-EAR ATTENUATION OF HEARING PROTECTORS

4.1 SCOPE OF SECTION

4.2 PHYSICAL REQUIREMENTS OF THE TEST FACILITY

4.2.1 Test signals

4.2.2 Test site

4.2.3 Test equipment

4.3 TEST SUBJECTS

4.3.1 Conditions for subject acceptance/dismissal

4.3.2 Previous experience with hearing protectors

4.3.3 Anatomical features

4.3.4 Otoscopic inspection

4.3.5 Age

4.3.6 Sex

4.3.7 Maximum hearing levels

4.3.8 Minimum hearing levels

4.3.9 Threshold variability

4.3.10 Spectacles and jewellery

4.3.11 Literacy

4.3.12 Number of subjects

4.3.13 Maximum number of tests per subject

4.3.14 Exceptions

4.4 PRODUCT SAMPLES

4.4.1 General

4.4.2 Custom-moulded earplugs

4.4.3 Product instructions

4.4.4 Variable position headbands

4.5 TEST PROCEDURE

4.5.1 Preliminary set-up

4.5.2 Test method

4.5.3 Re-determination of thresholds

4.6 COMPUTATION OF REAL-EAR ATTENUATION

4.7 COMPUTATION OF CLASS OF HEARING PROTECTOR

4.8 TEST REPORT

APPENDIX A - CALCULATION OF SLC80 AND CLASS OF HEARING PROTECTOR

A1 GENERAL

A2 CALCULATION OF SLC80

A3 EXAMPLE OF SLC80 CALCULATION

A3.1 Step 1

A3.2 Step 2

A4 DETERMINATION OF CLASS

A5 BIBLIOGRAPHY

APPENDIX B - QUALITY CONTROL TESTS

B1 SCOPE

B2 QUALITY CONTROL TESTS

B3 COMPARISON WITH THE ORIGINAL CLAMPING FORCE TEST VALUE

APPENDIX C - COUNTERBALANCING