Air
Purifiers: Everything You Need To Know But
Were Afraid To Ask
By David Barnaby and
Mercia Tapping
AllergyBuyersClub.com
INDEX
Every year, some journalist
pretending to be writing a responsible article
about air cleaning ambushes us. Inevitably,
it turns out to be some simplistic attention
getting tactic, trashing air cleaners uniformly.
What IS true is there are
number of air purifiers out there in the
marketplace; some of which are best sellers
to consumers, which have very questionable
effectiveness. Yet there is a reason why
the government reimbursed people for hepa
air filters if they lived near Ground Zero;
or why they recommend them for homeland
security or why hospitals use them in infectious
disease units. Yes, they do work, but some
of them not as well as you would want all
the time, and you need to know what you
are buying.
The problem is one of discrimination
and education. How does a consumer make
an educated choice? This is a subject about
which our staff could give chapter and verse[and
frequently do when people who telephone
us!].I cannot even begin to tell you how
many air cleaners we get in here to test
and which do not pass the cut. During the
last six months we have had machines to
test which smell either of plastic and ozone[which
is toxic],efficiency levels which are disgraceful,
replacement filter costs which are a rip
off, untruthful or misleading specifications,
shoddy materials; the list goes on and on.
There is a reason why AllergyBuyersClub.com
has garnered the reputation of being incredibly
knowledgeable about air cleaning, and David
Barnaby, the coauthor of this article, puts
prospective products through their paces.
We have attempted to reproduce
in this article, the kind of questions and
advice we would give you if you phoned us.
If you can absorb it all, this article tells
you everything you need to know, and if
you are confused, you can still phone us
up and we will keep our advice as short
and sweet as you like.
Do
You Need an Air Purifier for Allergen, Virus
or also Odor and Gas Control?
There are many choices for
the consumer in the marketplace. Your choice
of air purifier will be completely different
according to what you are trying to achieve.
For instance, if your main goal is to clear
the air of allergens, you should choose
an air purifier which would remove the large
particulates such as pollen with a pre-filter,
but also smaller allergens, which would
be particulates from 0.3 to 5 microns in
size. These smaller allergens include mold,
bacteria, animal dander, fumes, and house
dust mite allergens. A Hepa filter would
trap particulates of this size and remove
them from the air in your room. However,
it is important to note that more than 90%
of all particulates are 0.3 of a micron
and smaller in size. These are known as
“lung penetrating particles”
and are the ones most dangerous to your
health. Particulates of this smaller size,
include viruses, some bacteria and germs,
some house dust mite allergens, cat allergens,
smoke, soot, fumes, and smog.
 Since
most standard Hepa filters [and there do
exist some Hepa filters with enhanced filtration
capabilities such as IQAir]
would not be able to trap most of these
smaller particles, there are also some machines
that utilize ultraviolet light in combination
or as a standard alone machine, where the
rays will breakdown the DNA and RNA of the
microorganism, and while not “killing”,
they will sterilize those microorganisms,
thus preventing them from being able to
reproduce and grow. An Excellent example
of the this would be the CARE
Air Defense System air purifiers. A
word of caution; all ultra violet machines
are not equal and their quality and effectiveness
varies enormously. The most important factor
determining the effectiveness of ultra violet
light is whether the rays are strong enough
in the first place, which is referred to
as its dosage. Also, the rays need to expose
the microorganism to the light for a long
enough time in order for the DNA and the
RNA to be altered. Even if the ultra violet
light is not completely effective, having
one is better than nothing, because some
of the micro organisms will be sterilized
by the rays when they collide with the light
or “bump around” with a side
to side movement, so as not to move through
the UV chamber too fast.
If you need an air purifier
primarily for odor and gas control, you
would want an air purifier that will first
remove the majority of the particulates
in a pre-filter and then have the gases
and odors removed by the gas filter. Gas
molecules are very small so they cannot
be removed by even the finest Hepa filter.
They are 0.001 and smaller. Therefore, they
need to be physically removed by a substance
that will trap them in their many micro
pores. A good substance commonly used is
activated carbon where it is super heated
and steamed resulting in millions of tiny
pores. Each one of these pores will be able
to adsorb the gas molecules. Once the pore
cannot hold anymore of the gas molecules,
it is said to be saturated, which means
it will not be able to adsorb anymore gases
and odors. Another method of gas and odor
removal is through chemical absorption where
the gas molecule will be exposed to a chemical
agent where in combination with water molecule
a chemical reaction will occur whereby this
gas molecule will be broken down into a
harmless byproduct such as carbon dioxide.
A common substance used is alumina silicate,
alumina oxide, and potassium permanganate.
These are particularly effective at removing
your lighter molecular weight gases such
as formaldehyde.
Good candidates for odor and
gas control are the IQMultigas,
Clarifier and Allerair
air purifiers.
The
Size and Quality of the Hepa filter in your
Air Purifier.
The more square feet of Hepa
filter media there is in an air purifier,
the more particulates it will be able to
remove from the air before it becomes clogged.
Also the air purifier will be able to remove
more particulates with each pass. The quality
of the Hepa filter is very important both
in the material used and the design. The
pleats of a Hepa filter need to be uniform
so each one has the same efficiency of filtration.
If the pleats are too close together they
can restrict the air movement too much resulting
in a loss of airflow. Some Hepa filters
out there use synthetic materials and not
paper. Thin paper is the best material because
it will be both effective at removing the
highest percentage of the microscopic particulates
while not restricting airflow too much.
However, the better grades of Hepa filters
are extremely delicate and can be easily
damaged. This is why the better air purifier
companies will house the filter in such
a way as to protect the actual Hepa filter
material.
Good candidates here are the
IQAir
HealthPro, Clarifier and Allerair
air purifiers.
Lung
Damaging Particles
Lung damaging particles are
of most concern because of the fact they
are small enough to get through your sinus
cavities and into your respiratory system
while at the same time large enough not
to be exhaled out. Therefore, it is very
important when considering which air cleaner
to purchase to make sure it will be able
to filter all of these particulates. The
size range will vary from 9 microns to 0.3
of a micron in size. This is why the Hepa
filters have become so important to the
air cleaning industry.
 Particulates
in this lung damaging size range are some
bacteria, most molds, fumes, smoke, smog,
diesel exhaust, cat allergens, pollen fragments,
house dust mite allergens, settling dust,
and suspended atmospheric dust. All of these
particulates can cause an allergic reaction.
Keep in mind, it is still necessary to filter
out particulates smaller than these, but
particulates smaller than 0.3 of a micron
have a better chance of being exhaled out
of your respiratory system. However, some
of them will still remain in your lungs
to do damage. In addition, the American
Lung Association believes particulates that
have been ionized have a better chance of
sticking to your respiratory system so their
likelihood of being exhaled is low. Therefore,
an air cleaner’s ability to filter
out particulates in the 0.01 to 0.3 of a
micron in size is important, since this
would include some bacteria, viruses, some
pet dander, some house dust mite allergens,
and some of your smokes and smog. An excellent
example here would be the IQAir
HealthPro Plus.
Is
Ultraviolet Effective in Air Purifiers?
Ultraviolet [UV] light is
a known proven effective way to sterilize
germs, bacteria, mold, viruses, and other
microorganisms. However, these results are
achieved in a correct controlled environment.
For example, if a surface with germs on
it, is directly exposed to UV light with
enough intensity (dosage) for a long enough
period of time (exposure), the surface will
be sterilized. However, it becomes more
difficult to attain this control when you
try to sterilize microorganisms in an air
purifier. The biggest question in regard
to UV light in an air purifier, when the
micro organisms are moving through the air
purifier at a fairly high rate of speed
because of the fan, but are they exposed
to the rays of the UV light long enough
to alter the DNA and the RNA of the micro
organisms? There will be a higher efficiency
of sterilization of micro organisms the
lower the fan speed. However, if someone
is also trying to clean the air of other
particulates at the same time, there will
be a decrease in air changes by lowering
the fan speed, and thus a decrease in the
air cleaning capacity of the machine. Another
hybrid approach is to have a UV light that
bathes the Hepa filter with continuous light
which will kill all of the micro organisms
that have been trapped by the Hepa filter.
This means there will be no need to worry
about what is happening to all of these
bacteria and germs that are sitting on the
Hepa filter for such a long period of time.
However, there is also concern as to what
the rays from the UV light will do over
time to the material of the Hepa filter.
The Hepa material can become brittle and
start to break up over time when exposed
to UV light so the life of the Hepa filter
may become shortened.
The CARE
ADS air purifier is a great example
of an air cleaner where the company has
tested its effectiveness in medical systems
and are confident that their product will
work in all sorts of situations where virus
control is needed.
Carbon
or Other Types of Fill for Specialized Gas
Control for Air Purifiers
 There
are many different types of carbon available
to be used in gas filters ranging from coal
based to coconut shell. The main purpose
of carbon filters is to physically adsorb
the gas molecules into their pores. Activated
carbon filters will be best at removing
the VOCs and SVOCs, which are of a higher
molecular weight. However, carbon filters
will not be very effective in humid conditions
where the air contains a large amount of
water molecules. Carbon is also not effective
in removing the lower molecular weight gases
from the air such as formaldehyde and sulfur
and nitrogen dioxide. These require specialized
gas control ingredients made up of Chemisorbers
which will chemically remove these gases.
What Chemisorbers do is react with a water
molecule in the air and the gas molecule
to chemically break it down into a harmless
form such as carbon dioxide. This is chemical
absorption. Common Chemisorbers are alumina
oxide, alumina silicate, and potassium permanganate.
The amount of gas filter media is important
in measuring the effectiveness of a gas
filter but this is not the entire story.
Obviously, the more micro pores of carbon,
the more gas and odor can removed and the
longer the gas filter will perform before
all of its pores are saturated and need
to be changed.
What are just as important
are the particulate filters included with
the gas filter in the air purifier. If there
is an inefficient pre-filter before the
air encounters the gas filter, a great deal
of the micro pores in the carbon will be
used to collect the particulates not removed
by the pre-filter. Therefore, a gas filter
containing many pounds of activated carbon
could prematurely become saturated. The
design of the gas filter is also important
as to airflow. A gas filter with fine activated
carbon will cause a lot of resistance to
airflow. However, if the gas filter consists
of larger pellets the air will flow through
the filter easier. Also, a pleated design
can result in a larger surface area of carbon,
which would increase the efficiency of the
rate of gas removed since the gas molecules
will have a better chance of being adsorbed
with this larger surface area.
Excellent candidates here
are the IQAir
HealthPro, Clarifier and Allerair
air purifiers.
Technologies
Other than Hepa Filters for Air Purifiers
Worth Consideration
Hepa filters are an example
of mechanical filtration. The advantage
to this filtration method is there is no
reduction in its efficiency at removing
the particulates from the air over time.
In fact, a Hepa filter will become more
efficient as it collects more particulates,
because it is so fine. The only reason you
need to eventually change it is because
it will start to effect the airflow through
the air purifier, which will result in a
loss of air cleaning capacity and also may
damage the motor because of the heat that
may buildup. The disadvantage to this kind
of filtration is that these air purifiers
tend to be noisy, especially on the higher
speeds. Their filters are replaceable and
can be rather expensive, especially on the
more efficient air purifiers which remove
more from the air over a shorter period
of time.
The other types of air purifiers
are called electronic air purifiers and
they utilize a single or combination of
technologies to clean the air in a room.
An electronic air purifier works by charging
the particulates upon entering the machine
by an ionizer. This is a wiring mechanism
that creates an electrical charge; with
the outcome being the particulates are negatively
charged.
There are four different forms
of electronic air cleaning:
 1.
The first is called an electrostatic precipitator,
which consists of a series of metal collection
plates that are oppositely charged to the
ionized particles. Therefore, the particles
will be attracted to these metal plates
like a magnet with the net result being
the ability to collect particles as small
as 0.1 of a micron. There is a drawback
to this type of air purifier, which is as
the collection plates collect the particles,
and their surface area becomes covered by
the particulates, their ability to attract
the particles will decrease until the plates
are taken out and cleaned. In a good unit
you may start out at an efficiency of 80%
and degrade down to as little as 20%. Thus,
it is imperative you clean the metal collection
plates on a regular basis as frequently
as daily to weekly. These types of air purifiers
will generate a fair amount of ozone definitely
enough for you to smell and may be annoying
to some people. Most of these machines generate
safe levels of ozone.
One of the best examples of
this technology is the Friedrich
C90 air cleaner.
2.
The second type of electronic air purifier
uses a media charged filter. This means
it has a electrostatic filter that will
collect the particles by being oppositely
charged to the ionized particles and therefore
able to collect particles again as small
as 0.1 of a micron. This filter will start
out at a high efficiency as much as 80 to
90 percent but will decrease as the surface
area of the filter becomes clogged with
particulates. The biggest decrease will
be in the smaller particles, because remember
this is not a Hepa filter and it is not
able to mechanically remove the microscopic
particles, because it is not as fine and
thick a filter. It will however maintain
its ability to filter out the larger particulates
better than the electrostatic precipitator
because its filter media is small enough
to collect the larger particles without
having to rely on the opposite charging
attraction needed for the smaller particulates.
However, you will still have a decrease
in the efficiency to as low as 50% if the
filter needs replacing and it is not changed.
3.
The third type of electronic air purifier
is the negative ionizer. This machine attempts
to clean the room by basically eliminating
the particulates from the air. The particles
are not removed from the room just from
the air. The way it works is the particles
are drawn into the machine where they are
ionized and negatively charged. From there
they are sent back into the room where they
are attracted to the positively charged
walls, furniture, positive and neutrally
charged particulates where they collide
with them until they are heavy enough to
fall to the floor. The result is that the
air becomes free of particulates and the
particle count is reduced. The drawback
to this type of air purifier is that all
of your particles land up on the floor,
walls, and furniture. As the particles lose
their charge they will release themselves
from the walls falling back into the air.
Also, unless you are regularly vacuuming
and dusting, the particles will be kicked
back into the air when any air movement
occurs by a door being opened or someone
walking in the room. A major concern is
that if an ionized particle is inhaled,
it is more likely to stick to the walls
of your respiratory system thus increasing
the chance of an allergic reaction. The
advantage of these kinds of air purifiers
is that they will be quiet because there
is no resistance to air flow and there are
no filters .Also the tendency will be to
use them for treating a large amount of
air, because if a smaller, quieter fan is
used, it will still result in a large amount
of air being circulated through the machine.
Also, there are no expensive filters to
replace such as with Hepa filters and no
pre-filters that need to be cleaned. Still,
we tend not to recommend negative ionizers
except if they are used in conjunction with
other air cleaner technology.
4.
The fourth and definitely the most controversial
air purifier is an ozone machine. Its whole
premise is based on the use of ozone to
clean the air but its claims are very suspect.
The ozone machine manufacturers claim the
air is cleaned and the gases, chemicals,
and odors are removed from the air. However,
the ozone reacts with the chemical and it
breaks it down into another form of pollutant.
The question is whether this new form of
pollutant is even worse than the original
chemicals. Also, to be effective, it must
emit high levels of ozone which have been
determined to be detrimental to the respiratory
system. Therefore, you have a dilemma with
this machine, which is to run it at safe
low levels and have little effect, or on
high levels, where the concentrations could
be dangerous to humans. In addition, the
question of particulates in the air is not
even addressed, since there are no filters
to trap the particles. You may be familiar
with their use in the hotels where to prepare
a room for a customer, the machine is put
in place and the machine turned on high.
The windows and doors are closed and the
room is left unoccupied while the machine
is in operation, which is usually to remove
the smoke odors. Once the room is cleaned
hotel staff will go into the room, turn
off the machine, and open the windows to
air the room out and rid the room of the
ozone. Ozone is a concern to human health
and this has been well documented by the
EPA.
There are also air purifiers
that use a combination of a pre-filter to
collect the large particulates, and a UV
light. These air purifiers will emit ozone
into the room, which reacts with the gases
and odors in the room and chemically breaks
them down into another form.
In conclusion, the main advantages
to electrostatic precipitators are there
are no expensive filters to replace and
they are quieter than Hepa filters. The
disadvantages are, ozone is emitted and
there is a steady reduction in efficiency
as the metal plates become dirty, so regular
cleaning is imperative.
The main benefit of media
charged filter electronic air purifiers
are that they will be quiet and clean a
large amount of air. The disadvantages are
the cost of the replacement filters and
there will be a gradual efficiency drop
as the filter becomes dirty.
The main advantage to negative
ionizers are that there are no filters to
clean or change, and they will be quiet.
The disadvantage is that the particles are
not actually removed from the room, and
can work themselves back into the, thus
re-polluting the room caused by movement
such as a door opening and closing or people
moving about. Also, negative ionizers create
a good amount of ozone, so the odor and
human reaction either to the odor or toxicity
needs to be addressed. The advantages to
the fourth type of electronic air purifier,
the ozone machine, is debatable. They can
be dangerous and their air cleaning ability
is suspect. However, for smoke odor removal
after smoking or a fire they are the air
purifier of choice because of the low cost.
 With all these types of technologies
out there the only ones we would consider
would be the media charged filter type such
as the Blueair,
which uses the ionizer to chargethe incoming
particulates so the particulates will be
attracted to the electrostatic filters.
There is no ozone emitted by this air purifier.
Another one we would consider would be an
electrostatic precipitator as in the Friedrich
C90A, which uses the ionizer to charge
the particulates, which will be attracted
to a series of metal collection plates.
It will have a pre-filter to collect the
larger particulates and a post filter with
some carbon impregnated throughout to remove
gases and odors.
 An
AirFree
Sterilizer works by incinerating the
particulates at high heat at 400 to 600
degrees. It is effective at removing airborne
particulates of size 1 micron and smaller.
This would include germs, bacteria, mold,
viruses, pet dander, smoke, and house dust
mite allergens. Keep in mind, this is not
something you would want to use toremove
dusts, pollens, and other larger particulates.
Also, since it does not use a fan it is
not able to circulate the air in a room
and attain the proper number of air changes
to clean the air quickly of everything in
a room. The Airfree sterilizer works by
slowly over a 1- 3 week period removing
the airborne bacteria, viruses, molds, etc.
as stated above and it continued operation
will maintain the sterilized environment.
It is therefore an ideal machine for virus
and spore elimination.
Its most effective use is
to prevent mold from reoccurring in the
future. Each unit will sterilize an area
of 250 square feet with an average ceiling
height of 8 feet so it will control an area
of 2000 cubic feet. One of the three things
necessary for mold to grow is the presence
of air born mold spores. Normally, there
will always be an abundance of these because
they are in great supply in the outdoors
and some of them will always circulate into
the inside of your house. However, the use
of the Air free Sterilizer will eliminate
them so mold formation will become very
difficult.
The heated sterilization process
used by the Airfree Sterilizer is intriguing,
and backed up by an unusual number or laboratory
studies as to its effectiveness. Particularly
interesting about this technology is the
measurement of the residual level of contaminants
in a room after the testing period which
can be as low as 85% reduction from its
original levels which has exceeded our results
in testing of hepa filters. What is difficult
in all the study results we have seen from
any manufacturer is the rate of recontamination
which is a factor in real life. If you live
in a major city, your environment is constantly
being recontaminated at a pretty fast clip
so it is difficult to ever get completely
“pure air” even with large filters
going at full speed.
How
Serious is the Problem You are Trying to
Remedy?
It is very important to determine
how serious is the air quality problem you
are trying to solve. If you are dealing
with allergies, the more serious they are,
the purer the air needs to be around you.
One person with light allergies may feel
fine with a cheaper quality air purifier,
while somebody else with more severe allergies
may find that same machine to be completely
in ineffective and still be symptomatic
Also, the exact nature of allergies or sensitivities
is an important factor when choosing an
air purifier. Different air purifiers are
needed for those suffering from multiple
chemical sensitivities or asthma. If a person
has asthma, it is recommended they purchase
an air purifier with a gas filter to control
gases and odors, which can trigger an asthma
attack. People with multiple chemical sensitivities
can react to almost anything, so the correct
choice of air purifier is extremely important,
since this person could react to the material
that makes up the air purifier such as glue
on the Hepa filter or out gassing from plastic
parts. When dealing with gas, odor, and
chemical situations, the more concentrated
the amount of gas contamination with perhaps
a high rate of recontamination, the stronger
the gas filter needed. If you wanted to
control general cooking odors, you would
need a basic gas filter, while cigarette
and cigar smoke requires a very large and
powerful gas filter.
Sizing
Your Room and the Right Size Air Purifier.
The size of the room is a
significant factor when choosing an air
purifier because in order to properly clean
the air in a room, you will need to exchange
the air in the room several times each hour.
The reason for this is that initially the
air will have a certain pollution level
depending on your external environment and
activity inside the area you are planning
to clean and maintain. In the beginning
the air changes will be necessary to reduce
the pollution level until it is reduced
by around 80%. After this the continuation
of the air purifier will be to maintain
the cleanliness of the air. The more efficient
an air purifier is with each pass the less
air changes that will be needed to clean
and maintain the air quality. Factors affecting
how much you will need to clean the room
would be the construction of the room as
far as how much infiltration of pollution
would be allowed to enter the room each
hour. Also, how much activity is there in
the room as far as doors opening and closing,
people walking around, etc. This activity
will stir up all the dust and particulates
that has settled on the floors, furniture,
and walls. Normally, you will look for a
range of 2 to 8 air exchanges an hour with
2 air exchanges only being acceptable with
the most efficient of the Hepa air purifiers.
When cleaning the air for gases, odors,
and chemicals it will be better to run the
air purifier at a lower speed so the gas
molecules will have more contact time with
the activated carbon. This would also be
true for units utilizing UV light to sterilize
the particulates.
Where
are you Going to Place the Air Purifier
in your Room?
 The
placement in the room is important when
you consider your air purifier choices.
We recommend for bedrooms a quieter air
purifier with less air exchanges during
the night, than a family or living room
where there will be more traffic and faster
re-polluting of the air. Placement of the
air purifier in the room will always be
best if it is in the middle of the room.
However, since particulates and gases will
through diffusion maintain an equal distance
between one another, as the particle count
is reduced as the air purifier cleans, the
room, the remaining particulates will spread
out to maintain this equal distance. As
they move across the room, they will eventually
be drawn into the vacuum that is created
by the air purifier’s fan. Therefore,
placement of an air purifier on the sides
or ends of a room will be able to filter
the particles on the opposite side of the
room.
Noise
Level in Air Purifiers.
Noise level is a personal
choice because some people do not mind,
or even welcome a background white noise,
while some people cannot stand any fan noise
whatsoever. Also, when someone is purchasing
an air purifier for a bedroom, they are
usually looking not only for a quiet air
purifier but also a smooth running machine
that will not have an inconsistent pitch
and noise level. What is helpful is not
to make a purchasing decision solely based
on the area size a specific air purifier
can clean. The reason being a unit that
can clean 800 square feet will still do
an excellent job in a 200 square foot room
with one important additional benefit. Because
of the larger capacity air purifier, you
will be able to properly clean the smaller
room on the low or medium speeds, which
are almost always significantly quieter
on the larger Hepa air purifiers. If someone
purchases an air purifier that is tight
in its sizing capacity they will find they
need to run the unit on high most of the
time, and even the smaller air purifiers
are noisy on the high speed. The only reason
someone should not consider a larger air
purifier is because of the physical size
being too large for the room.
A perfect choice for a quiet
air purifier for bedroom use is the Blueair
501 and Blueair 402. For a small bedroom and
for portability consider the Hamilton
Beach series.
Automatic
Monitoring of Pollution Levels in a Room.
There are some air purifiers
which have an infrared detector that will
monitor the amount of particulates in its
vision. Initially, when turning on the air
purifier, it will automatically run itself
on the high speed, because the particle
count will usually be high. As the particles
in the detector’s vision are reduced,
it will turn itself down to the medium speed
and eventually to the lower speed. The idea
in theory is excellent but since the area
being measured is so small, the accuracy
of this automatic monitoring device is in
reality pretty minimal. A separate particulate
monitor is recommended.
The Hamilton
Beach Air Purifiers have this monitoring
system.
Efficiency
Level of your Air Purifier
Two critical things to consider
when measuring how effective an air purifier
is at performing, is the amount of air that
it can clean each hour and what percentage
of the pollution does it remove from the
air that is circulating through it. This
second factor is called the efficiency.
For example, if the particle count per cubic
foot of air going into the air purifier
is 1,000,000 particles and the particle
count of the air coming out after it has
passed through the filters is 300, than
the efficiency of the air purifier would
be 99.97%. Therefore, you can see how the
efficiency of the machine is important since
a machine that is only 60% efficient would
allow 400,000 particles to go back into
the room. The efficiency is important because
there are many air purifiers on the market
that have a Hepa filter but their relative
efficiency is undocumented. This only means
that the filter has been tested to remove
99.97% of all of the particulates that are
0.3 of a micron in size or larger. However,
this is when all of the particles in the
air contact the Hepa filter and none of
the air is able to bypass the filter itself.
Once you take the Hepa filter and install
it in the air purifier other variable are
involved. As the air is drawn into the air
purifier, some of the air can bypass the
filter media depending on the way the filter
is housed inside of the air purifier. As
much as 40 or 50 percent of the air can
pass by the filter media in some Hepa filter
based air purifiers resulting in poor performance.
Our most efficient machines
in our testing were the IQAir
series and the Clarifier series.
The
Importance of a Prefilter for your Air Purifier.
 The
pre-filter is one of the most significant
parts of an air purifier. Most pre-filters
are designed to remove particulates 5 to
10 microns and larger. This is useful because
the very large particles will be removed
from the air[such as pet hair or large dust
particles], which will protect the gas filter
media or the Hepa filter media from becoming
used up prematurely. However, you must realize
that the percentage of particulates in the
air that are 5 microns and larger is very
small. For example, if there are 1,000,000
in the air per cubic feet, there is normally
only around 400 to 800 particles that are
5 microns and larger. Therefore, much of
the particulate removal is still left for
the pores of the activated carbon of the
gas filter, if it is the next filter in
line after the pre-filter or the Hepa filter.
A large gas filter with 15 pounds of activated
carbon can become quickly saturated if it
has no pre-filter or the pre-filter is not
very efficient. Also, the Hepa filter is
too expensive a filter if it is used to
remove particles larger than 1 micron. The
best example of a pre-filter is the one
on the IQAir
Healthpro which is 100% efficient at
removing particulates 1 micron and larger.
In addition, it is 55% efficient at removing
particulates 0.3 of a micron and larger.
So as you can see this filter will remove
90% of all of the particulates in the air
and prolongs the life of the Hepa and gas
filters.
Filter
Change Indicator Lights
We find a filter change indicator
light to be extremely helpful, because someone’s
ability to actually see particulates in
a room to judge whether a hepa filter needs
replacing, or relying on smelling odors
to judge the life of the gas filter, is
not an accurate or scientific way to track
the life of the filters. In addition, you
would need to remember to check the filters
periodically to examine them. The best air
purifiers will have individual filters for
each of these purposes. A well-constructed
air purifier will have a separate pre-filter,
gas filter, Hepa filter, and post filter.
It will indicate when each of these filters
needs to be replaced. All of the guesswork
is eliminated, and you will not be running
the air purifier with filters are clogged
which should be changed, or be prematurely
changing filters, which is unnecessarily
expensive.
IQAir,
Clarifier,and Hamilton
Beach Air Purifiers have change filter
indicator lights.
Ease Of Changing Filters
This is something that is
often overlooked and can prove very frustrating
to the owner of an air purifier. The best
air purifiers are those requiring no tools
to replace the filters. Those units where
you simply pop out a door, pull the filter
to be replaced out and replace it with the
new filter are by far the easiest. Some
air purifiers require some considerable
disassembly, requiring tools; some are manifestly
more difficult than others. If it is tedious
and difficult to change the filters, the
average person will put off changing them
way beyond their optimal change dates. Also,
just because some manufacturers say their
pre-filters do not have to be replaced but
can be periodically vacuumed or washed is
a bit deceptive as the process of accessing
the pre-filter is very tedious and ignored
my most people.
The easiest filters on an
air purifier to change are the Blueair
and Hamilton
Beach Air Purifiers. The IQAir
is quite easy too when you have done it
once and the same comment applies to the
Clarifier or Allerair
series
Weight and Mobility of Your
Air Purifier
Most air purifiers are on
casters, so you will be able to move them
from room to room without having to physically
lift them. However, this is not helpful
if you need to carry it downstairs or upstairs.
In this case, it is easier if the air purifier
is lightweight. The Hamilton Beach Series
are the easiest just to pick up and carry
to the next room.
Upkeep Costs for an Air Purifier.
 This
is another factor which is often overlooked
by the potential purchaser of an air purifier.
An air purifier that costs $400 to $500
can end up costing from as little as $50
a year to maintain or as much as $200 a
year. You need figure out how often the
filters need to be changed and how much
they cost. Some air purifiers may have expensive
filters, but you may be able to go a longer
period of time before they will require
changing. You should be aware that the quoted
filter change intervals because can vary
significantly depending on how often the
unit is run and the pollution level of its
environment. For example, the Austin
Air manufacturer states you can go five
years between filter changes. However, we
have found the norm is more like three years
for all machines, given the real life conditions
under which it is used. It is also helpful
if the unit has individual filters to change
as opposed to one big expensive combined
filter to change. The reason why a combination
filter[hepa plus carbon] is a disadvantage
is because when the Hepa filter and the
carbon gas filter are combined, both filters
rarely will require changing at the same
time. Most of the time, the gas filter will
need changing before the Hepa filter. However,
if either side of a combo filter needs to
be changed, you are forced into replacing
the entire filter, which is an unnecessary
expense.
Air Purifiers, Ozone Emissions
and Outgassing.
Any ozone emission, which
is a toxic substance, is not desirable regardless
of whether the person has allergies, asthma,
or multiple chemical sensitivities. However,
the effects are usually worse for these
people. In general, ozone is an irritant
to the respiratory system. It becomes progressively
irritating as concentration levels increase.
The problem is that most manufacturers do
not monitor the ozone levels. Outgassing,
which can occur from the silicone used for
the gaskets and glues used to attach the
filter media to the housing, can outgas
and cause a reaction, especially for people
with multiple chemical sensitivities. If
you belong in this category you should look
for an air purifier where the pre-filter
and Hepa filter come before the gas filter,
so any out gassing that could otherwise
occur will be removed by the activated carbon.
Keep in mind, it is recommended anyway that
there be some type of filter after the carbon
gas filter, to remove any carbon particles
that may fall off as the air passes through
it.
A good air cleaner for those
with multiple chemical sensitivities is
the Allerair
series.
Central
Air Cleaners
Central air cleaners will
allow a person to clean all of the air in
their house with one unit. You should only
consider this type of air cleaner if you
have a central heating, cooling, or both
that circulate air throughout the house.
The way a central air cleaner works is that
it is tied in with the existing central
air system in the home. The central air
system will circulate the air back into
the rooms of the house through the ductwork
and out the supply registers and the air
will return back to the system through the
return ductwork. A central air cleaner is
installed by having the return air drawn
into the intake of the air cleaner and the
cleaned air then is circulated back into
the central air main return. It is recommended
to intercept the air at the end of the main
return just before it goes into the furnace
or air conditioner. The installation consists
of two openings in the main return at least
6 feet apart to prevent shortcutting. Ducting
is run from the first opening to the intake
of the air cleaner and then from the outflow
of the air cleaner back to the second opening.
The airflow of the air cleaner is only to
draw the air from the main system to clean
it and not to circulate the air throughout
the house. It is for this reason the central
air system needs to be running while the
air cleaner is running. A central air cleaner
is not strong enough by itself to push the
air through the HVAC system and out to the
rooms of the house and then back into the
system. We recommend setting the HVAC system
with the fan on, so the air will circulate
regardless of the temperature setting.
Keep in mind, a central air
cleaner will be able to filter out most
of the particulates and remove most of your
gases and odors but it will never be as
efficient as a free standing air cleaner
in a specific room exchanging the air several
times an hour. While the central air cleaner
will exchange the air in the house 2 to
4 times an hour because of all the registers
and duct work in the home 90% and better
efficiency is difficult. The big advantage
is if you have a 2000 to 4000 square foot
home, you will be able to clean the air
with one air cleaner as oppose to several
units and it will be quiet.
Furnace
Filters
An efficient filter in your
heating or cooling system can reduce your
particulate levels and hence air pollution
by up to 50%. As long as your central air
system is operating, all of the air will
circulate through this filter, so not only
will you be protecting your furnace and
air conditioner, but the incoming pollution
will be reduced. These filters are electrostatic
so the flow of air creates a charge where
the particulates are drawn toward the filter.
The particles are not charged like an ionizer.
Some of these filters are not replaceable
and require periodic cleaning every 1 to
4 months while some are replaced every 1
to 4 months. Keep in mind, these filters
will do nothing to remove gases and odors.
They are only for the removal of particulates.
In addition, they do not to replace an air
cleaner, because even the best filters will
only remove particulates down to 1 to 1.5
microns in size. In order to remove smaller
particulates you would need a Hepa filter
and the resistance of such a filter would
restrict the movement of air in the HVAC
system and cause problems.
Your
Air Purifier Manual
Instruction and information
from the manufacturer is extremely helpful.
In addition, you want to be sure you can
contact the dealer for after sales support
after you have purchased the air purifier.
They should be able to work with you, as
a liaison between you and the manufacturer
.A good manual will explain the filters
in the air purifier, how to set the unit
up if there is any assembly required, offers
troubleshooting advice, and gives you maintenance
information. A poorly written owner’s
manual can be very frustrating if you have
any questions or basic troubleshooting situations.
Style
and Your Air Purifier
The choice of style of the
air purifier is a personal choice. Usually,
if the air purifier is going to be set up
in a visible room such as the living room
or the family room the looks of the unit
will be important. Color will also be of
importance. This will be less important
if the unit is being purchased for a less
widely used room such as a basement. For
some, style will not be as important as
its level of effectiveness, but for others,
the styling is almost as important as choosing
a sofa for their living room or family room.
Some people do not want it to stick out,
but blend in with the styling of the room.
Keep in mind, the design of the inside of
the air purifier is more important. The
looks are strictly cosmetic. The exceptions
would be the intake and the outflow areas.
You do not want the inflow and the outflow
areas near each other because you will have
shortcutting, which is where some of the
air that has just been cleaned may be drawn
back into the inflow of the air purifier.
Also, you want the air to be sent back into
the room in multi directions and in a larger
area. It is better for the air to be circulated
back into the room in more than one direction.
Also, if the air comes out of one small
opening, it can be very uncomfortable if
a person is sitting close to it. The better
designs are where the air is drawn into
the air purifier through the bottom in all
directions and outflows at the top in all
directions from the entire perimeter of
the unit.
A good looking unit is the
Blueair
and wins our beauty pageant award. Good
multidirectional clean air systems are the
Blueair
and IQAir
air purifiers.
The
Warranty and Reliability of Air Purifiers.
This is an area that most
consumers concentrate on and is very important.
The old saying that you get what you pay
for is often true. If you buy a product
that is inexpensive with a short warranty,
often you will find yourself replacing the
unit. You may realize later on you would
have been better purchasing a more expensive
air purifier but one which was better built,
with the longer warranty. The best warranties
are those offering five years on the main
fan and motor parts. A reliable air purifier
should have no problems with the motor,
fan, and electrical components and controls.
The rest of the air purifier consists of
the filters, which need periodically cleaning
or replacement. Quality control is important
and any information you can glean about
the reliability and breakdown rates of air
cleaners is recommended.
The
Manufacturer’s Reputation.
Reputation of the manufacturer
is important. Chances are if previous customers
are unhappy, and there is published information
of a product’s past performance, you
are also going to have problems. Of course,
it is possible a good manufacturer may go
through a bad period on a particular product,
which is not reflective of the company in
general, or where the manufacturer has taken
customer feedback to heart and has acted
upon to prevent repetitive problems in the
future
Summary
In summary, the most
complete air cleaning system, assuming one
has a central air system in their home,
would be an efficient furnace filter along
with a central air cleaner. In addition,
a free standing portable air cleaner in
the bedroom and most frequently occupied
rooms of the house would complete the air
cleaning system. If you do not have a central
air system in your home, you want enough
air cleaning to attain a minimum of 2 air
exchanges with the most efficient of Hepa
air cleaners to as many as 4 to 8 air exchanges
with other types of air cleaners.
Click
here for more info on air purifiers
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Rhinitis
And What To Do About It
By
Dr Murray Grossan
 Rhinitis is a fancy
word for runny nose, drippy nose, congested
nose. Rhino is nose and (itis) is for inflammation.
Doctors have to use big words so they can
charge more.
The body tries to protect
itself. When a common cold or a toxic product
hits the nose, you sneeze to try to get
rid of the infected material. In addition
your body tries to dilute the toxin or virus
– the less concentrated the toxin
the easier it is for the body to correct
the problem.
That’s why you need
to drink lots of water for rhinitis. That’s
also why you drink lots of water for stomach
poison, in order to dilute it.
Allergic Rhinitis
You can have allergic rhinitis.
Here the body is “stupid”. Instead
of sneezing and dripping when you are around
a huge amount of dust, your nose doesn’t
react to a small amount of dust or whatever
you may be allergic to. Allergic rhinitis
varies in degree. One person has rhinitis
when he dusts the piano. Another gets it
when they enter the room where the dusty
piano is located. Some are so sensitive
that they sneeze when the enter the room
after the piano and the rugs have been thoroughly
dusted.
When we test a person for
allergies we need to know how sensitive
he is to the pollen or dust. So we dilute
our test materials
1:10
1:100
1:1,000
1:10,000
1:100,000
Sometimes a test dose of 1:100,000
may even be too strong. That is why we keep
resuscitation materials on hand in the allergy
office.
Allergic rhinitis often responds
to allergy pills such as Allegra, Claritin,
or dozens of others. Some patients get relief
from nasal sprays such as Flonase or Rhinocort.
Whichever works best for you, you must still
keep the bedroom free of dust and odors,
use unscented lipstick, avoid hot spices
and iced drinks.
Allergic rhinitis is like
arithmetic. It takes 10 to give symptoms.
Add, pollen, dust, fatigue, spices, getting
chilled and get 10. Subtract the spices
and you may get 8 – not enough to
give you symptoms. But when the pollen count
goes higher, this can get you up to 10 again.
So try to reduce the equation – less
dust, spices, odors, fatigue.
It is a good idea to check
out the pollen counts to see which pollen
is causing your symptoms. Then you can identify
which tree or weed is causing your problem.
In Los Angeles, allergic rhinitis
is worse when the Santa Ana winds blow.
This blows in dust and pollen from the surrounding
area. Most allergic persons are worse then.
When you drive, you MUST drive
with the windows closed. If the windows
are open, the faster you drive, the more
pollen goes into your nose.
Chemical Rhinitis
The new products keep coming
out faster than they can be properly scrutinized
for health factors. It is well known that
chrome, diesel, smog, Skydrol, all irritate
the nose. Most volatile solvents do too.
Your state occupational safety unit , OSHA,
can help you identify which products might
be harmful to you.
Bacterial Rhinitis
There are dozens of nasty
bugs out there, but some are nastier than
others. Some produce a chemical that paralyzes
the cilia and causes a serious infection.
This is why pulsatile irrigation may be
very helpful; the fewer the bugs are washed
away, and the quicker the cilia return,
the quicker your health is assured.
Is it sinusitis or rhinitis? Often it is
both. If the nose is inflamed, and the sinus
x ray is clear its just rhinitis.
If the sinus x ray shows disease and inflammation
and the culture taken from within the sinus
grows bacteria, then it is sinusitis.
Viral Rhinitis
This is the most common nasal
condition and is referred to as the common
cold. There are dozens of types that cause
cold symptoms, which is why there isn’t
a good cold vaccine available yet.
For most persons this lasts
a week and then they are OK. When it lasts
longer, it means that a sinus infection
has taken place as a result of the cold.
Why do some persons develop
a sinus infection after a common cold? Several
possibilities:
- Blowing your nose so hard
that the tissues swelled and blocked the
sinuses.
- A particularly virulent
cold virus
- Being fatigued, exhausted,
getting no sleep
- Some of the medications
dry out the nose so much that the cilia
couldn’t get rid of the toxic products
- Not drinking enough fluids
such as hot tea with lemon.
Treatment
I am appalled whenever I ask
my patient what they have in the medicine
cabinet. Thanks to the 12 billion dollars
spent on medicine advertising each year,
each of my patients have a minimum of 3
“cold” remedies in the cabinet.
Not that some aren’t
fine. But this idea that the advertisers
have promoted that the moment you have a
sniff or snort, you must spray your nose
and take their pills is stupid.
For most common colds, just
resting, hot tea, chicken soup will do it.
Some of the nose sprays rebound and you
get addicted. Some of the sprays have preservatives
such as benzalkonium that can make you worse.
Some of the pills that dry the nose dry
things too much and make you worse.
Notice that no one advertises
hot tea and chicken soup, and plain resting!
What they advertise are products that MIGHT
shorten the cold by one day in SOME persons.
Unfortunately, later on you learn about
the side effects of some of these products
that are the most advertised.
The worst cases are those
who panic the moment the nose feels stuffy
– immediately they use all kinds of
sprays and pills. And then they get anxiety
because of the “congestion”.
If they would just relax, rest, give their
body a chance, in most cases the symptoms
are over in a day or less. Instead, they
have used so much medication that the medicines
are making them jittery and nervous and
they feel worse.
Of course it the symptoms
persist or get worse, then its time to seek
relief, but not within the first hour.
Rx
1. Lots of fluids.
Especially tea, lemon and Chicken Soup
2. Avoid ice drinks. Avoid getting chilled.
3. Dress correctly. Don’t sit in
a draft
4. Rent a comedy video. Happy white cells
are stronger.
5. Drink enough so your urine turns light.
6. Don’t blow your nose hard! Be
gentle. Don’t force air if your
ears get blocked. It's OK to open your
mouth widely, but forcing the ear open
can push pus into the ear.
7. Warm compresses to the sinus area
OK, you say, all this is
lovely theory, but I’ve got to go
to work, take care of the kids, etc. what
can I do?
Sudafed is a decongestant
that helps many persons. Read the label
carefully.
Many patients claim to do
well with vitamin C. If the stomach tolerates
it, 500 mg is the maximum dose. Over this
amount can cause you to lose calcium.
Many patients get relief with
the Tylenol type “cold remedies”
and “flu remedies”. These are
reasonable formulas and can be helpful.
Benadryl is useful. Dries
you out and puts you to sleep. I have recommended
liquid Benadryl for kids who have colds
to help them sleep and help prevent colds
going into the ears.
You can be sure that what
works for one person may not work for another
and your doctor is the best source of information.
Prevention
If you only get a cold once
a year I don’t see any point in bothering
about it.
For those who get frequent
colds, there is a chemical called ICAM –
1 in the nose that is the portal of entry
for the common cold virus. For years my
patients insisted that by using the Hydro
Pulse® irrigation daily they prevented
getting a cold. Frankly, I never paid attention.
Then research started coming out that verified
this claim. Now I believe them.
If you are prone to frequent
cold infections, during the cold season,
consider daily Hydro Pulse irrigation. This
removes the ICAM –1 and may reduce
the number of colds you get.
If you are stuck behind a
diesel bus/truck and inhale the fumes, consider
rinsing the nose when you get home to remove
these products.
If you are in car with an
air bag blowing up, that powder tends to
stick in your nose and should be washed
out. I have seen persistent symptoms from
this powder.
If your workplace has bad
fumes, check with OSHA to see if these fumes
are dangerous for you. If it is a new product
that is upsetting you, have the doctor measure
your nasal cilia to see if there is a problem
due to those fumes.
For some reason I can’t
figure out, OSHA tells you to wash your
hands when you are exposed to certain chemicals
to remove them from your hands. They may
even advise always washing your clothes.
But they never tell you to rinse your nose
with saline to remove chemicals from your
nose! Many of my patients in certain industries
have been helped by simply rinsing the nose
to remove these chemicals.
Other suggestions at www.ent-consult.com
If you are a postal worker
and inhale a suspicious powder, immediately
rinse your nose with saline. Use a nasal
wash bottle or just cup your hands. You
may be washing out anthrax spores. One such
lavage product to keep handy is at www.sinus-relief.com.
In summary, if you are diagnosed
with Rhinitis, try the hot tea and rest
first.
Click
here for more info at the AllergyBuyersClub.com
sinus center
Top
|
If
you live on the East
Coast, you are aware
that we are saying out
here, "What summer?"
The weather has been
appalling, with endless
rain causing an enormous
amount of flooding,
mildew and mold problems.
Good
Health.
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