TABLE OF CONTENTS The level of sound (noise) is an important indicator of the quality of the environment. Ramifications of various sound levels and types may be reflected in health (mental and physical) and/or in aesthetic appreciation of an area. Because of the important consequences of a too-noisy environment, this resource, sound, is examined separately rather than under various other resource categories.
The sound (noise) in an environment is indicated by many attributes, but some important ones are
Physiological effects
Psychological effects
Communication effects
Performance effects
Social behavior effects
Definition of the attribute. Noise can affect the physiology of the human body in three important ways:
Internal bodily systems
Hearing threshold
Sleep pattern
Internal bodily systems are defined as those physiological systems essential for life support, that is, cardiovascular (heart, lungs, vessels), gastrointestinal (stomach, intestines), neural (nerves), musculoskeletal (muscles, bones), and endocrine (glands). Noise stimulation of nerve fibers in the ear may indirectly harmfully affect these systems. High-intensity noise (e.g., artillery fire, jet aircraft takeoff) constricts the blood vessels, increases pulse and respiration rates, increases tension and fatigue, and can cause dizziness and loss of balance. However, these effects are generally temporary and, to some extent, adaptation does occur. The process of adaptation is in itself indicative of an alteration in body functions and is therefore undesirable. High noise levels can also reduce precision of coordinated movements, lengthen reaction time, and increase response time, all of which can result in human error (Miller, 1971).
Hearing threshold
