Room Air Purifiers vs. Whole-House Air Purifiers by Mary Lou Derksen
There
are hundreds of air purifiers available for sale. Some are meant
primarily for the one room in which the purifier is located. Some are
promoted as being able to purify the air in the whole house. Articles
are written to tout one kind over the other, usually depending on which
one the writer has for sale.
Obviously there are benefits for either kind of purifier, but how can
you decide which is best for you? Some of the most obvious comparisons
are price, amount of noise, space taken, and ease of cleaning. In
discussing these four areas, we will assume, for the sake of
simplicity, that both room purifiers and whole-house purifiers do the
job of air purification well.
Initially, room air conditions are generally the least expensive.
However, if you were to purify the air in every room in the house, you
would generally have to buy a purifier for each room. At that point, a
whole-house purifier would be the most cost effective. However, there
are some so-called room air purifiers that use photo-catalytic
oxidation that can, given enough time (up to several weeks for very
large areas), purify all of the rooms on a single floor of a house.
Room air conditions, by the very fact they and their motors are located
in the room, are noisier than a whole-house purifier whose motor is
located in or near the furnace (and oftentimes is the furnace fan).
Obviously, if you are looking at how much space in a room a purifier
takes, the whole-house purifier would win hands down every time.
Depending on which kind whole-house purifier you choose, it may take up
a fair amount of space near the furnace.
Room air purifiers are often easier to get at to clean, but if you have
one in every room you have a passel of purifiers to clean. If you
choose a purifier such as the Air Oasis purifiers, there is very little
cleaning involved, so the number of purifiers is insignificant for that
consideration. Some say that the whole-house purifiers are harder to
get at, but this need not be so if you research before you purchase,
and choose one that is not difficult to clean.
There are a few websites on the internet that argue that there is no
such thing as a good whole-house air purifier — a discussion of some
of their arguments will follow. However, in October, 2005, Consumer
Reports stated that whole-house purifiers did a much better job than
their smaller room-purifier counterparts.
As with room air purifiers, whole-house air purifiers can use a variety
of purification methods. These generally include filters that replace
the usual furnace filters, and usually either need frequent cleaning
and/or replacing or are not very effective, HEPA filters, carbon
filters, electrostatic precipitators, and electrostatic filters.
One of the arguments that has been given against whole-house purifiers
is that it is impossible for these cleaners to pull dirty air from
rooms that are “far” away from the central air return area in the
building. That thinking is either out-of-date, limited to certain kinds
of heating systems or made up of faulty thinking. If you have a furnace
/ air conditioner with ductwork in your home, then almost every room
has a cold-air return that draws the air from those rooms and through
the ductwork to the furnace or air conditioner. The air is then
redistributed to all of the rooms. I know that at certain times the
grates over the cold-air returns in the rooms of my house collect more
dust than any other part of the room, so I know that dirty air is
getting into that system! And the fact that heated or cooled air is
getting to all the rooms demonstrates the efficiency of redistributing
that air.
One article states that if you use an air-handler system (such as those
by AllerAir), you are using two fans all of the time: one in the air
handler, and the furnace fan. However, if you have an air purifier in
every room, how many motors are running all of the time?
This same article states that ultraviolet lights in the central HVAC
system can’t clean dust from the air, and that they can send harmful
ozone levels into the home air. I have not seen any scientific studies
or explanations, but I know of a number of instances where just
installing a good ultraviolet light system has reduced the dust and
dirt in the vent system. I also know that if you carefully choose the
right ultraviolet light system, such as one from ComTech, there is
never a problem with ozone levels.
Another article states that the only way to remove radon from your home
is to have an appropriate whole-house air purifier. In order to remove
a gas such as radon with a whole-house air purifier, you would likely
need a system that has some sort of carbon filtration system.
The only way to know what air purification system is best for you is to
know your budget, the health needs of your family, the area in which
your home is located and how large of an area needs to have the air
cleaned. Often a combination of several kinds of purification processes
will be needed to meet your health needs. Research the field and come
up with the best air purifier for you!
About the Author
Mary Lou Derksen has been involved in a variety of health-related
jobs since 1976, included nutritional counseling and mental health
counseling (as a licensed counselor). She also taught junior high and
high school classes in a 1-room school house setting. Never ready to
settle down to a stale retired life, she has now entered the field of
air purifications systems. http://www.magnamics.com