NOISE MEASUREMENTS

Noise testing should be done measurement laboratory with current accreditation.

Noise is a sound with a certain frequency that is perceived as too loud (excessive intensity). It is often a threatening factor, unwanted sound or noise caused by the activity of a person, machine or installation in an open area or in a room.

Noise emitted to the environment comes not only from industrial and commercial facilities, but also from road, rail and air traffic, as well as from farms and various types of infrastructure.

We can distinguish different types of noise according to their source. There are the following types of noise:

– Communication noise (from road, rail, air traffic, etc.).

– Industrial noise (from industrial equipment, technological installations, fans, air conditioners, vehicles moving on the project site, etc.).

– Noise in buildings – inside the buildings from various types of installations, e.g. water, boiler rooms and technical equipment of buildings, communication routes, ventilation units; concerning public places, e.g. noise in rooms where people stay.

Car transport, air transport, industrial installations and other local sources that often cause a subjectively perceived annoyance (e.g. sound systems in premises, restaurant gardens or shooting ranges) can be classified as the most unpleasant causes of noise for humans.

The rules regarding noise emissions are set out in the Environmental Protection Law. In order to control the emission (intensity) of noise in the environment, measurements are made to verify whether the noise standards dictated by law are complied with.

Measurements make it possible to identify the source of excessive noise. Thanks to them, we are able to prevent similar future exceedances by implementing specific actions that will lead to noise reduction below the thresholds considered acceptable, which in turn should ensure an acceptable level of acoustic emission.

Measurements of noise emitted to the environment are made during the day and at night using professional measuring devices.

Usually, the measurement results are made in relation to the existing acoustic background (i.e. sounds emitted in a given environment, but not coming from the measured source) and show where the noise comes from (from which source).

The results obtained on the basis of the measurement are included in the report and compared with the applicable legal requirements. In the event of discovering exceedances of the permissible values ​​for a specific type of terrain, the entity emitting noise is obliged to reduce the emitted noise below the permissible thresholds, and if this is not possible, to limit or cease operations.

Periodic noise measurements in the area of ​​economic activity are carried out when:

– decisions on the permissible noise level were issued

and/ or

– an integrated permit was issued, specifying the frequency of measurements.

Periodic noise measurements are usually made once every two years.

Appropriate atmospheric conditions must prevail when taking noise measurements.

Noise measurements are carried out in meteorological conditions specified at a height of not less than 3,5 m above ground level, not exceeding:

1) conditions specified by the manufacturer in the instrument manual;

and

2) the following boundary conditions, if they are stricter than those allowed by the manufacturer:

1. air temperature from -10°C to 50°C,
2. humidity in the air from 25% to 90%,
3. average wind speed up to 5 m/s,
4. atmospheric pressure from 900 hPa to 1100 hPa.

If it is necessary to perform measurements in conditions that differ from the above-mentioned temperature or humidity values, it is necessary to justify this deviation in the measurement report and additional analysis of its impact on the reliability of the measurement and on the uncertainty of the result.

Noise indicators are noise parameters defined by the A sound level expressed in decibels (dB).

We distinguish:

• indicators used mainly for making acoustic maps i  environmental programs against noise by state and local government institutions - LDWN and LN.

and indicators of more interest to companies and institutions emitting noise.

• Target pointers control of the conditions of using the environment for one day:
• LAeqD- equivalent sound level A for the time of day   from 6.00 am to 22.00,
• LAeqN- equivalent sound level A for the time of night  from 22.00 to 6.00 XNUMX.

The legal acts set the permissible noise levels as indicators LDWN, LN, LAeqD and LAeqN for types of areas differentiated by the type of development:

• residential development,
• hospitals and nursing homes,
• buildings related to the permanent or temporary stay of children and youth,
• spa areas,
• recreational and leisure areas,
• residential and service development;

Another type of measurement are noise measurements at the workplace.

Every employer has a duty to provide employees with safe working conditions – this is one of the employer's key responsibilities.

It should be ensured that the workplace is properly lit and that the employee maintains the correct posture while performing work. First of all, acoustic conditions are important - noise standards should not be exceeded at the workplace. If they are likely to be exceeded, appropriate protective equipment must be provided to the employee.  

In unfavorable conditions, an irreversible injury may occur, which may lead to damage to the employee's hearing, but also to deterioration of his well-being.

Exposure of a worker to high-intensity noise over a long period of time is harmful. It can affect the employee's performance and motivation,

The employer should order noise measurement at the workplace within 30 days of starting the activity.

In the event of a change in the device, technical or technological conditions affecting the changes in the conditions of work, noise measurements at the workplace should be performed again.

It is also necessary to repeat the measurements after a year, when noise above 0,5 NDN was recorded at workplaces. It is necessary to repeat the measurements after two years, when noise at the level of 0,2 to 0,5 NDN was recorded at the workplaces.