Factors that Affect Air Quality
Earlier chapters in this manual described different kinds of harmful agents. Chemicals, infectious and physical agents can all cause poor air quality that results in illness and discomfort.
Chemical exposures
Chemicals that cause health problems come from many sources. Chemicals can enter the building from the outside through the ventilation system. Workers are also exposed to chemicals from materials and activities inside the buildings. The chart below shows common sources of chemical exposures in buildings.
Infectious agents
People bring infectious agents into the workplace. The risk of infection is higher in workplaces such as hospitals and other health care facilities, shelters, schools and day care centers. Biological agents can also enter through the ventilation system.
Building conditions can also lead to the growth and spread of biological agents. Moisture aids the growth of fungus and molds. The bacterium that causes Legionnaires’ disease lives in the standing water in cooling towers.
Physical agents
The right amount of heat, humidity and air movement are important for comfort. These factors are also important for preventing sickness. For example, molds and germs can multiply and spread easier when the air is humid.
| Chemical Exposures in Buildings | |
| Cleaning and maintenance | cleaning chemicals pesticides |
| Equipment and work activities |
copy machines giving off ozone office supplies such as glues and correction fluids printing machines laboratory use of chemicals |
| Building materials and furnishings |
damaged asbestos insulation, fireproofing or flooring lead from paint formaldehyde from furniture, curtains and carpeting |
| Human activities | smoking cosmetics, soaps, lotions preparing food |
| Outside pollution | exhaust from vehicles industrial pollution dumpsters and other unsanitary debris near air intakes leakage from underground fuel tanks, landfills |
