Environmental Engineering Reference
In-Depth Information
In some parts of the world (but not in the U.S.), candle manufacturers
use lead-containing wicks. Such candles produce large quantities of very
fine lead aerosol particles. These candles are imported into the U.S. and are
estimated to comprise 3% of all candles sold.
C. Propane-fueled burnishers
Burnishers are used to polish tile floors in relatively small-to-large buildings.
They may be powered electrically, or be propane-fueled. Propane-fueled
burnishers can produce significant emissions of CO and other combustion
by-products.
Research has shown that employees using propane-fueled burnishers
are intermittently exposed to several hundred ppmv CO. Case investigations
of their use in poorly ventilated buildings (e.g., a day-care center) have
recorded CO concentrations >500 ppmv and high carboxyhemoglobin
(COHb) levels (as high as 26% COHb) in those exposed.
Propane-fueled burnishers are widely used in large retail stores and
other buildings by building staff or commercial cleaning companies. The
actual extent of their use is not known and little is known about potential
exposures in occupied buildings. Their use may explain, in part, news stories
of illness complaints consistent with CO exposure in a number of retail
establishments.
D. Propane-fueled forklifts
Forklifts powered by engines utilizing propane are widely used in Amer-
ican industry and warehouse operations. In such environments they are
usually the major cause of elevated CO levels and worker exposures. Con-
centrations that average 10 to 50 ppmv are not uncommon, with higher
levels in travel lanes.
Forklifts and similarly powered equipment pose IAQ problems when
they are used in buildings with attached office spaces or other multipurpose
functions. Significant contamination of office environments with CO and
other combustion by-products can occur as a consequence. Office CO levels
of 50 to 75 ppmv have been recorded. Office buildings attached to ware-
housing operations are at particular risk of CO and other combustion by-
product exposures.
E.
Ice resurfacing machines
Ice skating and hockey rinks in North America, northern Europe, and Japan
are subject to considerable emissions and associated high concentrations of
a variety of combustion-generated contaminants. Such emissions are asso-
ciated with the use of fuel-powered ice resurfacing machines (commonly
called Zambonis). Typically these are propane- or gasoline-fueled; less com-
monly, diesel fuels are used.
