INDUSTRIAL environments require ventilation to reduce expo- sure to excess heat and contaminants that are generated in the
workplace; in some situations, cooling may also be required. Ventilation
is primarily used to control excess heat, odors, and hazardous
particulate and chemical contaminants that could affect the health
and safety of industrial workers. Control of excess heat and contaminants
can best be accomplished by using local exhaust systems
whenever possible. Local exhaust systems exhaust heated air and
contaminants at the source of the heat and contaminants and may
require lower airflows than general (dilution) ventilation. Chapter
30, Industrial Local Exhaust Systems, supplements this chapter.