About Noise and Noise Meter
The production of sound comes from the vibration of objects. If everything is still, there will be no sound! For example, the human voice is due to the vibration of the vocal cords.
The high and low (pitch), strength (loudness) and timbre of the sound are called the three elements of sound. The pitch of the sound is determined by the frequency of the vibration, the higher the frequency, the sharper the sound.
The strength of the sound is determined by the vibration amplitude (amplitude) of the sound wave. The larger the amplitude, the higher the energy of the sound wave, and therefore the louder the sound. Generally, we use decibels (dB) to express the loudness of sound. The difference in timbre is determined by the waveform.
source of sound
1. Noise: Noise sources are mainly factories, entertainment venues, construction projects, and traffic noise.
2. The sound of music, TV, electrical equipment, pleasant musical instruments and songs... or the sound broadcast on TV.
3. Sounds produced by nature: the sound of running water, the sound of birdsong...
4. The sound of human speech and the sound of animals. Such as the teacher's speech, the orchestra singing.
5. The sound produced by mechanical equipment and office equipment, such as the sound produced by factory machinery during operation, or the sound of fax machines, printers, and computer typing in the office... the impact of sound on the human body
Noise damage: The most common cause of inner ear damage is noise. All kinds of noise in civilized society will accelerate the degeneration and aging of the inner ear. Specifically, exposure to 90 decibels for more than eight hours, 95 decibels for more than four hours, and 100 decibels for more than two hours can damage the inner ear. The impact of loud sounds on the human body:
1. Noise can reduce hearing ability and even become one-time deafness.
2. Noise can cause abnormal mood, irritability, irritability and other psychological effects.
3. Noise can cause psychological effects such as accelerated heartbeat, increased blood pressure, and changes in sleep cycle.
Pleasant and appropriate volume of sound will relieve physical and mental tension, make people relax and restore spirit. It can also change the atmosphere, concentrate attention, relieve stress, help fall asleep, relieve sadness, stabilize emotions, enrich sensibility, and eliminate physical and mental exhaustion.
