GB/T 2888-91 Measurement Method for Noise of Fans and Centrifugal Blowers
This standard specifies the noise measurement methods and requirements for fans and centrifugal blowers. This standard takes the A-weighted sound pressure level as the basic noise measurement index, and provides the requirements for the measurement of sound pressure level as well as the sound power level expressed in dB(A).
This standard does not apply to the special measurement methods for harmonic noise, impact noise, etc.
This standard applies to various types of fans and centrifugal blowers.
The test shall be conducted in the reverberation chamber or soundproof box meeting the requirements of this standard. The sound pressure of the test point shall be measured with the corresponding sond level meter to obtain the sound pressure level of the corresponding frequency band of the test product. The A-weighted sound pressure level of the product should be calculated according to the formula specified in this standard.
The measurement accuracy meets the requirements of this standard under the given conditions. If the measurement conditions are different or the environment is complex, the measurement accuracy may be affected, and it is necessary to supplement or modify the actual measurements according to the actual situation.
Under the test conditions specified in this standard, the frequency weighting A-weighted sound pressure level should meet the following requirements:
1. General fans and centrifugal blowers should comply with GB/T 4417-1984 Assessment and limits of noise from fans and centrifugal blowers;
2. For fans and centrifugal blowers installed in commercial and office buildings, the A-weighted sound pressure level should not exceed 50 dB (A) at 1 m;
3. For fans, blowers and centrifugal blowers installed in hospitals, classrooms, research and development rooms, production test instrument rooms, and other rooms that need to be kept quiet, the A-weighted sound pressure level should not exceed 45 dB (A) at 1 m.
The A-weighted sound pressure level data measured must be marked and recorded as specified in this standard, including the type of product, the power of the product and the measurement results of the sound pressure level.
The A-weighted sound power level data measured should also be marked and recorded according to the requirements of this standard, including the type of product, the sound power level of the product, the size and the measurement results of the sound pressure level.
In summary, this standard provides the requirements for noise measurement of fans and centrifugal blowers. That is, taking the A-weighted sound pressure level as the basic noise measurement index, supplemented by the noise test of sound power level expressed in dB (A), the noise measurement conditions should be in the reverberation chamber or soundproof box meeting the standards. The A-weighted sound pressure level should meet the requirements of this standard. The reported data should be recorded according to the requirements of this standard.
