tailieunhanh - DEFINITIONS CONVERSIONS and CALCULATIONS for OCCUPATIONAL SAFETY and HEALTH PROFESSIONALS - CHAPTER 6

Âm thanh và tiếng ồn Sự quan tâm chung trong chủ đề này xuất phát từ tỷ lệ phát triển ổn định tại nơi làm việc công nghiệp hiện đại ngày nay, âm thanh và / hoặc nghe tiếng ồn gây ra suy yếu (chủ yếu là một phần, nhưng đôi khi, gia hạn, thậm chí đến mất thính giác tổng số). Sự khác biệt giữa âm thanh và tiếng ồn là chủ quan. Âm thanh được coi là một cái gì đó thú vị hay hữu ích, chẳng hạn như âm nhạc [dễ chịu] hoặc lời nói hữu ích]. Tiếng. | Chapter 6 Sound and Noise The general interest in this topic stems from the steadily growing incidence in today s modern industrial workplace of sound and or noise-induced hearing impairments mostly partial but occasionally extending even to total hearing loss . The differences between sounds and noise are subjective. Sounds are considered to be something pleasant or useful such as music pleasant or speech useful . Noise in contrast is thought of as being unpleasant consisting of such things as the sounds of a table saw cutting wood or a fingernail scratching a chalkboard. This chapter will focus on the factors parameters and relationships that permit an accurate assessment of the potential for physiological damage caused by the ambient noise levels that exist in the workplace. RELEVANT DEFINITIONS Categories of Noise Continuous Noise An unbroken sound made up of one or more different frequencies of either constant or varying sound intensity sound pressure level is referred to as Continuous Noise. If such a sound is constant and unvarying in its amplitude it would be referred to as steady Continuous Noise. The alternative to this would be varying Continuous Noise. Continuous Noise is a fairly common occurring phenomenon - both in the industrial and the natural environment. In the natural environment one might regard the sound of a waterfall as steady Continuous Noise while the sounds of wind blowing through a forest would be in the varying category. In the industrial environment the sound of a rotating electric motor . a fan a pump etc. would be steady Continuous Noise while the operation of a floor waxer relative to a fixed observer would be varying Continuous Noise. Continuous Noise is an extremely useful concept. In assessing the potential hazards of any noise filled environment one attempts to quantify the existing noise pattern in terms of the steady Continuous Noise that could in theory replace it without altering any of the adverse effects that might be .