The increased noise level affects human health. It is established that excess of acceptable level of noise influence leads to increase in excitability of nervous system, blood circulation violations, impairment in memory and perception. Measurements of noise are defined by the corresponding standards and are provided with special measuring means - audio-noise meters.
It is required to you
- Audio-noise meter, screw-driver
Instruction
1. Make sure that the measuring instrument of noise conforms to requirements imposed to devices of this class of accuracy. As an example we will consider the widespread Testo 815 audio-noise meter belonging to the second class of accuracy. In technical data sheet of the device there has to be a mark that the audio-noise meter underwent metrological certification in the relevant services and the key parameters which are subject to measurement, extreme values of the measured sizes and an error of measurement are specified.
2. Establish device measurement range. Carry out its calibration for what put the device the microphone to the calibrator and establish the range of 50-100 decibels. Turn on the calibrator and modify indications of the audio-noise meter by means of the screw-driver.
3. Establish a temporary delay on the noise measuring instrument. Depending on the nature of the measured noise install the delay regulator in one or the other possible provisions. The first situation (Fast) is applied measurement of noise of the construction equipment and mechanisms. Use the provision Slow for measurement of noise of machines, printers, copiers.
4. Set waiting time by means of the special button on the control panel of the device. Establish if necessary noise measurement range. In the considered device the preset measurement range is 32-80 decibels.
5. Check correctness of fastening of the microphone to the device, direct it towards a source of noise and perform measurement. Try to take measurement directly at a noise source as the sound can be reflected from walls. The human body also is a noise source therefore you hold the device not closer than 50 cm from the body.
6. See kept in the device the measured noise parameters, if necessary enter data in a special notebook with the indication of the place, noise measurement time and also other significant features of a situation in which measurement was taken.