GB 31422.1-2025 Hearing protective equipment—Part 1：Earplugs English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing thorugh draft translation, self-check, revision and varification) will be delivered upon being ordered.
ICS 13.340.20 CCS C 73
People's Republic of China National Standard
GB 31422.1-2025
Replaces GB/T 31422-2015
Hearing protective equipment—Part 1: Earplugs
Issued on 2025-08-29 Implemented on 2026-09-01
Issued by State Administration for Market Regulation
Standardization Administration of China
Contents
Foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions
4 Classification
5 Technical requirements
6 Marking
7 Information provided by manufacturer
References
1 Scope
This document specifies the technical requirements, marking, and information to be provided by the manufacturer for earplugs.
This document applies to all types of earplugs designed to reduce noise and protect human hearing.
2 Normative references
The following documents contain provisions which, through reference in this text, constitute essential requirements for this document. For dated references, only the editions cited apply. For undated references, the latest edition (including any amendments) applies.
GB/T 12903 Terminology for personal protective equipment
GB/T 46342—2025 General test methods for hearing protective equipment
ISO 4869-2:2018 Acoustics—Hearing protectors—Part 2: Estimation of effective A-weighted sound pressure levels when hearing protectors are worn
3 Terms and definitions
Terms and definitions established in GB/T 12903 and the following apply to this document.
3.1
Hearing protective equipment/Hearing protector
Personal protective equipment designed to protect hearing from excessive noise stimulation.
3.2
Passive hearing protection
Hearing protection method that relies solely on product design and material type without electronic components to provide external sound attenuation.
3.3
Earplug
Hearing protective equipment (3.1) inserted into the external auditory canal or blocking the entrance of the external auditory canal.
3.4
Formable earplug
Earplug (3.3) made of compressible material that requires shaping by the wearer before insertion into the ear canal and will rebound to fit the ear canal after insertion.
3.5
Pre-formed earplug
Earplug (3.3) pre-shaped in a specific form that does not require the wearer to shape it before insertion.
3.6
Custom-moulded earplug
Earplug (3.3) made from impressions of the wearer's concha and external auditory canal.
3.7
Headband
Component of hearing protectors that applies a certain clamping force to ensure the earplug fits tightly against the external auditory canal.
3.8
Banded earplugs
Earplugs (3.3) connected by a headband (3.7).
3.9
Disposable earplug
Earplug (3.3) that cannot be cleaned and is typically discarded after a single use.
3.10
Re-usable earplug
Earplug (3.3) that can be cleaned and used multiple times.
3.11
Sound attenuation
Difference in hearing threshold between a given test signal with and without hearing protection.
Note: Sound attenuation is expressed in decibels (dB).
[Source: GB/T 7584.1—2004, 3.8]
3.12
Protection performance
Percentage of cases where the effective A-weighted sound pressure level when wearing hearing protection is equal to or less than the predicted value.
Note 1: The protection rate is often selected as 84% (equivalent to the constant α= 1. In this case, the subscript of the attenuation value is omitted).
Note 2: The case refers to the overall situation when a person wears a certain hearing protector in a specific noise environment.
Note 3: The subscript numbers indicate attenuation values calculated by different methods.
3.13
Assumed protection value
APVfx
Sound attenuation value of a hearing protector at a given protection rate x and a specific octave band frequency f.
3.14
Predicted noise level reduction
PNRx
Difference between the A-weighted sound pressure level LA of the noise environment and the effective A-weighted sound pressure level when wearing hearing protection, selected for a given protection rate x and noise environment.
3.15
High-frequency attenuation value
Hx
Predicted noise level reduction PNRx when given noise is (LC - LA) = -2 dB, for a selected protection rate x and hearing protector.
3.16
Medium-frequency attenuation value
Mx
Predicted noise level reduction PNRx when given noise is (LC - LA) = +2 dB, for a selected protection rate x and hearing protector.
3.17
Low-frequency attenuation value
Lx
Predicted noise level reduction PNRx when given noise is (LC - LA) = +10 dB, for a selected protection rate x and hearing protector.
3.18
Single number rating
SNRx
Value subtracted from the C-weighted sound pressure level LC to estimate the effective A-weighted sound pressure level when wearing hearing protection, for a selected protection rate x and hearing protector.
3.19
Level-dependent earplug
Earplug (3.3) equipped with a sound restoration circuit.
3.20
Sound restoration circuit
Electroacoustic device that can reproduce lower-intensity external sounds in the ear canal and limit high-intensity sound reproduction through a level-dependent gain function.
3.21
Criterion level (H)
A-weighted sound pressure level of noise H when wearing level-dependent earplugs with the sound restoration circuit set to maximum volume, corresponding to the first instance where the A-weighted equivalent diffuse field-related sound pressure level exceeds 85 dB(A).
3.22
Criterion level (M)
A-weighted sound pressure level of noise M when wearing level-dependent earplugs with the sound restoration circuit set to maximum volume, corresponding to the first instance where the A-weighted equivalent diffuse field-related sound pressure level exceeds 85 dB(A).
3.23
Criterion level (L)
A-weighted sound pressure level of noise L when wearing level-dependent earplugs with the sound restoration circuit set to maximum volume, corresponding to the first instance where
