Handbook of Environmental Engineering

17Indoor Air Pollution

Shelly L. Miller

Department of Mechanical Engineering, University of Colorado, Boulder, CO, USA

17.1 Introduction

Because over 80% of our time is spent indoors, we are significantly influenced by the air we breathe in the indoor environments in which we spend our time. The indoor air environment is not an exact reflection of outdoor conditions. There are many unique characteristics and activities that happen indoors including cigarette smoking, cooking, building material emissions, and consumer product use, which are examples of determinants of indoor but not outdoor air quality. Table 17.1 summarized the typical air pollutant concentration in indoor environments. The main factors that influence the quality of the air we breathe indoors are:

• Hazardous pollutants emitted both indoors and outdoors.
• Meteorology and climate, which modifies both outdoor air pollution and the indoor environment.
• Building ventilation conditions including infiltration, natural ventilation, and mechanical ventilation.
• Pollutant decay and removal processes in indoor air and on surfaces.

Table 17.1 Typical indoor pollutant concentrations.

Source: Adapted from Wadden and Scheff (1983).

Pollutant	Concentration	Location
Carbon monoxide	2.5–28 ppm	Offices, restaurants, bars
Nitrogen dioxide	0.005–0.317 ppm	Homes with gas stoves
Respirable particles	100–700 μg m−3	Smoking restaurants, residences
20–60 μg m−3	Nonsmoking restaurants, residences
Total suspended particles ...