Classification of occupational hazards at workplaces - Part 4: Occupational exposure to noise
1 Scope
This part of GBZ/T 229 specifies the classification principles and methods of work(job) exposed to industrial noise at workplaces.
This part is applicable to the classification management of work(job) exposed to industrial noise.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated reference, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GBZ 2.2-2007 Occupational exposure limits for hazardous agents in the workplace - Part 2: Physical agents
GBZ/T 189.8-2007 Measurement of physical agents in workplace - Part 8: Noise
3 Terms and definitions
For the purpose of this document, the following terms and definitions apply.
3.1
industrial noise
noise generated during production
3.2
steady noise
noise with A-weighted sound pressure level fluctuation < 3 dB
3.3
non-steady noise
noise with A-weighted sound pressure level fluctuation ≥ 3 dB
3.4
impulsive noise
noise with duration ≤ 0.5 s, interval > 1 s, and sound pressure RMS change of A-weighted sound pressure level ≥ 40 dB
3.5
work(job) exposed to noise
work(job) with sound that is harmful to hearing and health or may cause other hazards, and the equivalent continuous A-weighted sound pressure level of 8 h/d or 40 h/week noise exposure ≥ 80 dB
3.6
A-weighted sound pressure level
LpA, LA
sound pressure level measured with A-weighted network
3.7
equivalent continuous A-weighted sound pressure level
LAeq,T, LAeq
within the stipulated time limit, if A-weighted sound pressure of a certain continuous steady noise has the same mean square A-weighted sound pressure with time-varying noise, then the sound pressure level of the continuous steady noise is the equivalent sound pressure level of the time-varying noise, in decibel (dB)
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Classification
5 Principle of classification management
Annex A (Normative) Instructions for correct usage
Annex B (Informative) Classification example
