Noise Meter - Standard Provisions
In order to make the measurement results of the sound level meter produced by various countries in the world comparable with each other, the International Electrotechnical Commission (IEC) has formulated the relevant standards for sound level meters and recommended them to be adopted by various countries, and the IEC651 "Sound Level Meter" standard was adopted in Stockholm in May 1979, and the national standard of China for sound level meters is GB3785-83 "Electrical and Acoustic Properties of Sound Level Meters and Test Methods". 1984 IEC also adopted IEC804 "Integral Mean Sound Level Meter" international standard. IEC adopted IEC804 "Integral Mean Sound Level Meter" international standard, China and 1997 promulgated GB/T17181-1997 "Integral Mean Sound Level Meter". They are consistent with the main points of the IEC standard ** In 2002, the International Electrotechnical Commission (IEC) issued a new international standard IEC61672-2002 "sound level meter". This standard replaces the original IEC651-1979 "sound level meter" and IEC804-1983 "integral average sound level meter". China has formulated JJG188-2002 "Sound Level Meter" according to this standard. According to the new standard, the sound level meter can be divided into general-purpose sound level meter, integral sound level meter, spectrum sound level meter, etc. According to the accuracy can be divided into 1 level and 2 levels, two levels of sound level meter of various performance indicators have the same center value, only the allowable error is different, and with the level of the number of figures increases, the allowable error is relaxed. According to the volume can also be divided into desktop, portable, and pocket sound level meter. According to its indication method can be divided into analog indication and digital indication sound level meter.
Noise meter - classification
1, from the measurement object, can be divided into environmental noise (sound field) characteristics of the measurement and the measurement of the characteristics of the sound source.
2, from the sound source or sound field time characteristics, can be divided into steady state noise measurement and non-steady state noise measurement. The non-stationary noise can be divided into periodic change noise, irregular change noise and impulse sound.
3、From the frequency characteristics of the sound source or sound field, it can be divided into broadband noise, narrowband noise and noise containing prominent pure tone components.
4、From the precision of measurement requirements, it can be divided into precision measurement, engineering measurement and noise census.
