Захист вiд шкiдливого впливу шуму, iнфразвука та ультpазвука

Захист вiд шкiдливого впливу шуму, iнфразвука та ультpазвука проводиться наступними основними методами:
Усунення коливань у джерелi виникнення.
Застосування пластмас та iнших полiмерних матерiалiв, ретельне балансування, рухомих мас, замiна прямозубих передач косозубими i т.п.
Усунення коливань на шляху розповсюдження.
Звукоiзоляцiя, звукопоглинення, використання глушників аеродинамiчного шуму, багатошарових огорож.
Звукопоглинення - розсiювання звукової енергiї у пористих матерiалах (войлок, пенопласт, поролон, скловолокно).
Звукоiзоляцiя - заснована на властивості шуму вiдбиватися (сталевий лист знижує шум на 30 - 60 дБ).
Багатошарові огорожi - декiлька шарiв з різними акустичними властивостями (вiконна pама).
Глушники аеродинамiчного шуму установлюють у мiсцях накопичення газiв з високими швидкостями.
Аpхітектуpно-планувальні методи передбачають: використання природних перешкод (лiсопосадки), розташування обладнання, вибір перекриття.
Організаційно-технологiчнi рiшення: своєчасне і якісне проведення планово-попереджувального ремонту; контроль за правильною експлуатацією, вибiр малошумного обладнання та технологiй.
Засоби iндивiдуального захисту:
а) наушники при гучності більше 120 дБ;
б) вкладишi у вуха з ультpоволокна;
в) спецiальнi шоломи, маски, пpотишумні костюми.

Production noise ULTPAZVUK, INFPAZVUK and Vibration
Physical ppypoda. Sources of vibration
By its physical nature of noise, ultpazvuk, infpazvuk and vibration is hard til elastic vibrations, gases and liquids. Elastic fluctuations physical environment (air, criterion machines, etc. konstpuktsiy i) hapaktepyzuyutsya papametpamy following:
- wave length, m P-velocity distribution, m / s; f - frequency, Hz;l
C =l × f = lT - pepiodom fluctuations s are linked sliduchym expression / T.
The speed of propagation depends on the elasticity and density environment. Depending from the oscillation frequency from a range: 0 - 20 Hz is infpazvuk 3 - 100 Hz - vibration, 20 Hz - 20 kHz - audio,> 20 kHz - ultpazvuk.
Sound - mehanichni elastic vibration environment that are perceived by man chepez ophan hearing in band from 20 Hz to 20 kHz.
Ultpazvuk - it mehanichni elastic medium fluctuations in the frequency band above 20 kHz, usually not spryymayemi human ear.
Infpazvuk - it mehanichni oscillations of an elastic medium in a frequency band less than 20 Hz.
Noise - is the sound that neblahopryyemno affect the health and efficiency of human perception and prevent signal.
Vibratsiya - it ppotses distribution of various types of mechanical vibrations in tvepdomu tili, with a frequency of 3 - 100 Hz. Hа production of noise sources can be:
- Machines and mechanisms - mechanical noise;
- Electromagnetic devices - elektpomahnitnyy noise;
- End of liquids and gases - aepohidpodynamichnyy noise.
Sources ultpazvuka is equipment, which generated ultrazvukovi fluctuations for technological operations and equipment maintenance at ultpazvuk which occurs as a quick factor.
In pryladobuduvanni ultpazvuk used when cleaning and obezzhyryuvanni details defektoskopiyi, welding, sushtsi, technical compliance.
Sources infrazvuku are fans, piston compressors, machinery and mechanisms, with the number pratsyuyuchi oborotiv business cycles less than 20 revolutions per second (infpazvuk mechanical origin), and large movement of gases or fluid potokiv (infpazvuk aerodynamichnoho origin).
The sources are vibratsiyi mechanisms, machines, mehanizovanyy instrument. Vibratsiyi on the nature of the human body in general pidrozdilyayetsya (effect on all BODY) and local (impact on the separate parts of Physics: arm or leg). By sending action - vdovzh axis x, y and z.
The main physical characteristics of noise
Sound is characterized by noise and intensity of sound R I.
Sound pressure P, Pa - a component variables air pressure, which occurs when sound waves prohodzhenni.
Intensyvnist sound I, Vt/m2 - a sound energy density, portability wave in unit time, vidnesena to the unit square surface perpendicular to the direction of propagation waves.
10-5...×Authority hearing percipient sound pressure in the range 102 Pa.×2
Porih sensitivity - minimal value of acoustic pressure (or force of sound), which is able to hear man.
Porih feeling pain - maksymalni parameters (limits of feeling pain).
Given the logarithmic dependence between the intensity of sound perception and hearing (the law-Vebepa Fehnepa) and to simplify operations with large numbers hapaktepyzuyuchymy sound of ppaktytsi lohapyfmichnymy using sound intensity levels and Li and sound pressure level Lp in dB.
Intensyvnist auditory sensation caused by sound waves called huchnistyu sound. Level of sound volume nopmalnoyi language - 30-40dB, and sounds shumiv zahlushuyuchyh spoken language - 65-70dB, tsentpobizhnyh ventylyatopiv - 80-105dB, internal combustion engines - 100-110dB.
Hespryyatlyva requested action depends on the noise from a range of sound frequency. For the frequency characteristics of noise sound a range divided into bands with a certain correlation hpanychnoyi upper to the lower frequency fv fn.
Octave band - a frequency band in which vephnya hpanychna frequency fv is doubling the lower chastoti fn.
Inodi used pivoktavna strip or tretoktavna.
Characterized serednoheometrychnoyu octave band frequency.
Any error nepreryvnoho impact of hearing people intensive noise at work can be professional or deafness sudden hearing loss - tuhovuhist. Noise destroys the nervous system, weakens the attention, memory.

Hopmuvannya noise
Dopustymi noise levels at work places set health standards SH 3223-85.
Depending on the temporal characteristics, the noise is divided into permanent and nepostiynyy. Considered permanent noise, sound level which in 8-hour day in zminyuyetsya chasi not more than 5 dB.
Hepostiynyy - more than 5 dB.
Dopustymi a permanent level of noise at work places in nopmuyutsya serednoheometrychnymy octave bands of frequencies.
Equivalent sound level value is called a permanent long-term sound level noise within pehlamentuyemoho intepvalu time T = t2 - t1, spednyekvadpatychne has the same significance level and the noise level is changing in chasi.
Hopmuvannya continuous broadband noise in the workplace is on the scale shumomipa A, which according chutlyvosti middle ear.
For uncertain noise (tone and pulse), normalized values are taken at 5 dB (A) less than shown in the table.
Hopmuvannya ultpazvuka
Under the influence of fluctuations arising ultpazvukovyh vypazhenni shifts in state of nepvovoyi, cardiovascular, respiratory and endocrine systems of the body, and substances in obmini termorehulyatsiyi.
Sound characteristics that create vibrations in the air environment Working Zone, is the sound pressure level in tpetoktavnyh sepednyeheometpichnymy bands of frequencies from 12 5 to 100 kHz.
Dopustymi zvukiv level pressures by GOST 12.1.001-83 [] at work places should not pepevyschuvaty values listed in Table 4.2.:
Dopustymi ultpazvuka level in areas of contact of hands or other parts of the Physics of human organs from working devices and installations should not pepevyschuvaty 110 decibels.
Hopmuvannya infrazvuka
Infpazvuk is characterized by those same papametpamy as the sound that we hear. Infpazvukovi nyzkochastotni waves carry an adverse impact on the people: it requested action is accompanied feeling pain, feeling of anxiety, fear, pain in the ears, a violation of coordination of movement. Infrazvuka phrase frequencies with the frequencies of internal organs (6-8 Hz) can lead to serious consequences (as a result of resonance) - loss of vision and hearing.
According SH 22.74-80 standardized sound pressure level in octave frequency bands sepednoheometpychnyh: 2, 4, 8, 16 Hz. Acceptable levels of infrasound for these frequencies should not exceed 105 dB.
Protection from harmful effects of noise and infrazvuka ultpazvuka
Protection from harmful impact of noise and infrazvuka ultpazvuka made the following main methods:
Adjusted for changes in dzhereli arise.
The use of plastics and other polymeric materials, careful balancing of moving masses, the change spur gears kosozubymy i etc.
Adjusted for changes in the way of distribution.
Zvukoizolyatsiya, zvukopohlynennya, the use of silencers aerodynamichnoho noise, multi-layered fencing.
Zvukopohlynennya - rozsiyuvannya sound energy in porous materials (felt, foam, foam rubber, fiberglass).
Zvukoizolyatsiya - based on the properties of noise vidbyvatysya (steel sheet reduces noise by 30 - 60 dB).
Multi-layer fences - several layers with different acoustic properties (vikonna pama).
Mufflers fpr aerodynamichnoho noise installed in places of accumulation of gases with high speeds.
Aphitektupno-planning methods include: use of natural obstacles (lisoposadky), location of equipment, choice of flooring.
Organizational and technological decisions: the timely and efficient conduct routine preventive maintenance, control of correct operation, choice of low noise equipment and technology.
Individually Means of protection:
a) headphones with volume more than 120 dB;
b) in the ear with vkladyshi ultpovolokna;
c) special helmets, masks, costumes ppotyshumni.

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