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Охорона праці - Moskalova V.М.

4.7 Noise, ultrasound and infrasound

4.7.1 Vibrant noise is the yogi's basic characteristics

At zv'yazku with tehnichnim progressom vidbuvayetsya rizke posilennya acoustical background in the be-yak region of perebuvannya mneni, the battle with the noise of meness nin sotsialnne znachennya.

The sound of the noise is vinicic in case of mechanical colitis near a solid, gazopodibnom and rare sediments.

For phisic sutnistyu sound - tse hvilepodibne rozpusyugzhennya mehanichnyh colvalnye ruchiv frequent pruzhnogo sredovischa.

Over the course of a day, noise is the sound of sound, and negatively affects the organisms of people, zavazhuyuchi їy in roboti vidpochinku.

The main parameters, which characterize the sound is the amplitude of the collusion, the shvidkist rozpusyugzhennya dovzhini hvil.

Sounds kolivannya in be-ya middling vinikayut todi, if pіd dієu zbuudzhuychih forces zarushuєtsya yogo стаціонанний стан. Spots of the middle of the way to start kolovatisya vidnosno poslovnya rivnivagi, stvoinyuchi hvili sonic oprichnyh deformitsiy uaslesidok rhythmic stisnennya y rozrizhennya chastok sonic field. The skin point of the sound field is characterized by a sound of a vise (P, Pa). In the phase of the stamping of the sound tics, the positive is positive, in the phase of expansion - vid'emny.

Sonic tisk - tse rіznitsa mіzh mittєim znachennyam poznogo tisk i serednіm znachennyam ussku, scho sposteriagyatsya vysisutnosti sonic field.

In the presence of sound hvil, the energy is transferred to the sound, and the sound is called the intensity sound.

Intensity to sound - tsenergya, yaka to be carried in spacious sound hvileyu through a surface of 1m Perpendicular to the straightness of the extended sound hvilli for 1 second (W / m ).

Швидкість поширення звукових хвил залежить від пружних властове середовща (у повітрі 334 м / с).

Frequency storage of noise is characterized by the yogo spectrum. The spectrum of the spectrum can be low-frequency (up to 400 Hz), mid-frequency (400-1000 Hz), high-frequency (1000 Hz).

For the size of the interviews, the sounds, sounds, noise, and discrete and sotsylny noise.

Behind the nature of zmіn, scho vіdbuvayutsya in chasі, shumi бувуть стабільними й перервними. Stabilny noise at chasі zmіnyuyutsya vozbuttyєvo, and perervniy moe periodichno shvidke zrostanya енергії іїї recession through pevni pausi.

The sound of its own sunset is the colval of the rub. However, the sound of the lyudin is not skrynny sprimeima yak sonic subdivision. Hearing Aid people are reagu tilki on ti kolivalnyi ruhi, yakі vidbuvayutsya z pevnoyu frequency. Lyudina nikrasche shoe sounds in the range from 800 to 4000 Hz.

The minimum value of the sound power, the speed of the sound, the sound is called the threshold (threshold of sensation), and it becomes 10 W / m ( ). Minimal tisk, a certain lyudina sprimayє yak sound, at frequencies of 1000 Hz become Pa ( ). The upper boundary, for the sound of a wiklik, vzhe bolivovі vіdchuttya vіdpovadaє sili sound 10 W / m , And behind the sound of a gripe - Pa.

Otzhe, інтенсивність to sound on porozi bolovogo vidchuttya in 10 Разів перевищує force of sound on porozі chuttivostі, and behind the sound of a tick - up to 10 Разів. Різниця між bolivim threshold and threshold sensuality is great, it is not audible in acoustical rozrawnkah vikoristvuvati absolutes.

To characterize the acoustic phenomenon of the English language O.G. Bell (1847-1922r) Ввів спеціальну a scale of acoustical odnitsyn yak nybіlsh об'єктивну і таку, що відповідає фізіологічній сутності сприйняття. For the scale of the skin on the advancing riven sonic-power level, I alternate between 10 raziv. For example, the power of a single sound is greater than 10, 100, 1000 times, then for a logarithmic scale, you can convert it to 1,2,3 odnitsy (lg10 = 1 і т. Ін). Logarithmic odinitsya, scho vidobrazhaє tenfold zbіlshennya іtensivnostі sound pіvnyanno з іншим in acoustics nazivayetsya white.

Vuho mneni zdatne sprimati zminu were sounded in 10 times the Menshu for white, that in practice zastosovyt oditnitsu in 10 raziv menshu, yaka distala name decibel (dB).

Otzhe, bel і decibel - tse umovnі odіnitsі, yakі pokazuyut naskil'ki daniy sound (I) in the logarithmic scale, I change the minds of porn chutlivosty ( ). Valichiny, scho vimiryuyutsya such a rank, nazivayutsya rivni іntenivstnosti noise ( ) Abo the sounds of the sound ( ):

, Abo (24) (25)

The power of sound is proportional to the square of the sound clutter, the formula for viznachennya sound ticu is such a vigil:

(B) (25) (26)

Rіvenь intensity intensity sound for acoustic acoustics, and rіven sound sound - at оцінці його дії на оргаізм человени, оскільки organ hearing is senseless not to intensity sound, but to the middle of a sound wave.

Viznachennya rіvnya іntensivnostі sound for skin frequency vimagalo velikogo kіlkosty vimiryuvan, that's all the auditory frequency range sublayut on 8 sonic octaves. For skin octavi, the mean geometric mean of the frequency, Hz, is calculated.

, (27)

De , - inferior lower and upper frequencies, Hz.

The value for the skin octaves is 63, 125, 250, 500, 1000, 2000, 4000, 8000 Hz.