ABSTRACT
In this chapter we deal with these five factors in turn. Other environmental factors such as radiation and microbiological pollution (e.g., bacteria, molds) are not discussed in this book. Guidelines on the maximum allowable exposure are given for each of these factors, followed by possible measures for reducing the exposure. In general three types of measure can be applied to reduce or eliminate the adverse effects of environmental factors:
At source (eliminate or reduce source)• In the transmission between source and man (isolate source and/or man)• At the individual level (reduction of exposure duration, personal protective • equipment)
The presence of high noise levels during a task can be annoying and, in time, result in impaired hearing. The first symptom of impaired hearing is a perceived difficulty in understanding speech in a noisy environment (party, pub, etc.). Annoyance, such as interference in communication or reduction of concentration, can occur even at relatively low noise levels. Annoyance and impaired hearing can be avoided by setting upper limits for noise levels. Noise levels are expressed in decibels, dB(A). Table 4.1 illustrates a few examples of noise levels.
