Precautions for the application of sound level meter in road traffic noise measurement
As long as you choose a suitable sound level meter, according to the detection standard, you can get the noise value that meets the standard.
1. The measurement should be carried out under the weather conditions of no rain and no snow, and stop the measurement when the wind speed reaches 5 m/s or more. The microphone is equipped with a windshield during measurement.
2. Select a certain traffic artery as the measurement road section, and the measurement point is selected on the sidewalk beside the road between two intersections;
20 cm from the edge of the roadway, the distance from the intersection here should be greater than 50 m. Arrange 5 measuring points on the measuring road section and draw the measuring point layout diagram.
3. Use a sound level calibrator to calibrate the measuring instrument, and the deviation should not be greater than 0.5dB.
4. Continuously measure traffic noise for 20 minutes, and use 2 counters to record the number of large vehicles and small vehicles respectively.
5. Repeat the above measurements at 5 different measuring points on the same road section.
Is a noise detector the same as a sound level meter?
Simply put, noise detectors include sound level meters, but the concept is broader and includes individual sound exposure meters.
The essence of sound is fluctuation, elastic wave. When the sound source vibrates, it causes the vibration of the nearby air particles. Depending on the inertia and elastic properties of the air, the vibration of the air particles spreads around in the form of waves, forming sound waves. The direction of particle vibration is parallel to the direction of wave propagation, which is called longitudinal wave. The waves in the air are called density waves. Sound waves can travel through gases, liquids, and solids.
Sound pressure: the difference between the pressure and the static pressure in the medium when there are sound waves. The unit is Pa.
Noise: From a physiological point of view, all sounds that interfere with people's rest, study and work, that is, unwanted sounds, are collectively referred to as noise.
Noise pollution is a kind of physical pollution.
With the further development of urbanization, industrialization and transportation, and the increase of population density, people pay more and more attention to noise pollution, and the proportion of complaints among many environmental problems is increasing year by year. Therefore, noise pollution has become an important part of environmental monitoring.
