Noise and vibration protection

Noise and vibration protection

Noise and vibration protection

Noise and vibration protection is an important part of population health protection, especially in conditions of close proximity to sources of negative impact to residential buildings.

What are noise and vibration? Acoustic noise is an oscillatory movement of particles of elastic medium, which has negative impact on sound-sensing apparatus of organisms and perceived as undesirable. Originally, noise can be mechanic (as a result from operation of machines and equipment), aerodynamic (occurs in gas environment), hydrodynamic (occurs in liquid environment), and electromagnetic (occurs among electromechanical devices under the influence of magnetic forces. Vibration is the mechanical oscillations of elastic medium that is characterized by increasing and decreasing of movement of material particle. Therefore, mechanic noise or vibration is occurred because of operation of machines and production equipment. The main indicators of value or force, noise and vibration are oscillation frequency, which measured in Hertz (Hz). According to the oscillation frequency, noise is divided on high frequency (more 1000 Hz), mid-frequency (400-1000 Hz) and low frequency (less than 400 Hz). At ranges, which are not tangible by human sound-sensing system for high frequencies noise with frequency more 20 kHz, is used definition – ultrasonic, for ultralow frequencies noise with frequency less than 20 Hz – infrasonic. People perceive vibration oscillations from a part to 8 kHz, and if more – heat sensations. If the value of vibration is over 16 Hzб it goes with noise. For determining noise or vibration level, it is necessary to conduct laboratory researches by authorized organizations with special equipment. MCL, LLC proposes conduction of laboratory researches for determining frequency of noise and vibration.

More often, noise and vibration become a danger for human health after longtime impact in case of their oscillations in normal ranges. Particular danger for human is vibration with oscillations from 4 till 8 Hz, because own movements of several organs of abdominal cavity have the same frequency, and 30 Hz that correspond the frequency of body movements. Acoustic noise is capable to provoke increasing of human arterial tension, nervous breakdowns and diseases of sound-sensing apparatus. Ukrainian legislation («Protection of territories, buildings and constructions from noise» SCN В.1.1-31:2013, «Residential housings and constructions» SCN В.2.2-9-2009) clearly determines maximum permissible limits of noise and vibration oscillations. The maximum permissible limit of noise must not be over 85 dB. Also, Ukrainian legislation standardizes vibration speed, which, for example, on frequency of 16 Hz must not be over 0,0015 meter per second. For residential housing was approved a norm of noise limit, which must not exceed 55 dB at day and 45 dB at night.

Sanitary-hygienic zone which established for enterprises also includes noise and vibration which can cause after their activity. If enterprise achieves constant noise and vibration limit through installing specific equipment which allows construction and operation of residential and similar housings in sanitary-hygienic zone, enterprise has to organize and justify possible allocation of residential housings within sanitary-hygienic zone and to conduct certain legal actions for reducing SHZ.

For reducing noise and vibration load from mechanic equipment or other objects of infrastructure, specialized equipment or materials with absorbing and shielding (reflecting) capabilities are used. For example, industrial enterprises which installed vibration absorbing equipment, use rubber cushioning materials, or in case of large-sized equipment which installs on separate ground not related with building base. In protecting of noise which caused by production equipment, this equipment is covered by noise absorbing materials.

If using of local measures is insufficient and general noise and vibration limit is over maximum permissible limits, business entity can order determination and implementation of specific project decision and measures for compliance of hygienic standards of noise and vibration. Such services are provided by MCL, LLC which has the biggest experience in conducting similar works in Ukraine.