Examples of Everyday Exposure
Daily routines expose many people to potentially harmful substances, including particles smaller than 2.5 microns in size (yellow bars), toxic volatile organic compounds (red bars) and carbon monoxide gas (gray
line). The Environmental Protection Agency has set formal standards for outdoor exposure to such particles (daily average limit shown) and to carbon monoxide (eight-hour average limit shown), but acceptable limits for exposure to various toxic volatile organic compounds have been more difficult to assign. Estimates (for particles and the predominant volatile organic compound) or direct measurements (for carbon monoxide) in various "microenvironments" in one man's day illustrate how much one's exposure can fluctuate, with the highest levels of exposure typically arising during indoor activities.