Environmental Engineering Reference
In-Depth Information
sures when used on a regular basis. As a consequence, regular candle burn-
ing should be avoided to prevent carbon deposition and soiling of interior
building surfaces.
Total or partial avoidance can be applied to the use of UF-bonded wood
products. Despite significant reductions in emissions from particle board,
hardwood plywood, and medium-density fiber board (MDF), use of such
products in high volume has the potential for producing elevated health-
effecting HCHO levels. Such elevated HCHO exposures are likely to occur
in new mobile homes (approximately 50% of new mobile homes are con-
structed with particle board decking).
Avoidance can also be applied to the use of CCP products. Avoidance
would be appropriate for individuals who have a propensity for develop-
ing rashes and allergy symptoms. Total avoidance would be desirable when
clerical workers develop severe symptoms on exposure. Less sensitive
individuals may choose to minimize (but not totally avoid) contact with
CCP materials.
Other products consumers may wish to avoid or use only under certain
conditions include cool mist humidifiers, biocidal materials, fiberglass duct-
board, and certain air cleaning devices. Significant microbial growth in water
reservoirs of cool mist humidifiers, with subsequent aerosolization, com-
monly occurs when units are not cleaned regularly. Sonic humidification
devices pose another indoor contamination problem, i.e., deposition of min-
eral dusts on interior building surfaces when water with a moderate-to-high
mineral content is used. Such mineral deposits can be avoided only by using
distilled water. Most consumers do not, however, use distilled water as rec-
ommended. Cool mist humidifiers should, in most cases, be avoided. Steam
humidification in residences poses fewer risks of indoor contamination.
Fiberglass ductboard is widely used to form supply air trunklines and
return air ducts in residences. Some products may produce irritating odors
in response to heating system activation. Because such duct material is
porous, it has the potential for collecting organic dust that can serve as a
medium for microbial growth and subsequent building contamination.
These potential problems may be avoided or reduced by the use of galva-
nized steel ductwork.
Biocides and pesticides are often used indoors. Their use should be
limited to circumstances where major infestation problems must be con-
trolled or can be controlled without significant biocidal exposures. Major
infestations may include cockroaches, fleas, or ants. To minimize indoor
contamination with cockroach-controlling pesticides, generalized or broad-
cast spraying should be avoided. It is more desirable and appropriate to use
crack and crevice spray applications or the use of poison baits. Poison baits
can also be used for ant control. Biocides are often used to treat interior
residential duct surfaces after duct cleaning. The use of biocides for such
applications is not known to have any useful purpose, and because com-
monly used biocides such as glutaraldehyde are potent irritants, their use
should be avoided.
