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filtration is your first line of defense in achieving
Indoor Air Health but is often overlooked. This is reflected
in minimal provision for air cleaning in design and a legacy
of indoor air quality issues. H.V.A.C. Manufacturers, ventilation
system designers and mechanical contractors need to raise the
spector of filtration as an equal partner in the delivery of
air for the comfort and health of people who occupy the spaces
entrusted to their care. The problems associated with poor indoor
air quality are well documented but you may be surprised to
learn how simplistic and cost effective the solutions can be
through understanding the role that better filtration design,
application and maintenance plays. This presentation attempts
to ask the IAQ stakeholders to give equal space, time,
and thought to air filtration for the delivery of acceptable
Indoor Air Health. |
| 51,840,000
Cubic Feet of Filtered Air
for only 79¢ |
| In deference to a sensitized
society becoming ever more paranoid about the quality of the
air in homes, schools and the workplace, a 79¢ air filter
continues to dominate the filtration products market place.
The standard filtration install in today's high efficiency
furnaces, heat pumps and room air conditioners affords, at
best, a 1" slide rail track for an air filter. Failure to
provide space for adequate filtration is exacerbated by reducing
the amount of fresh air to occupied spaces in the drive towards
energy cost savings. Cynical as it may appear, inadequate
filters, by design, have created market opportunities for
H.V.A.C. service companies, duct cleaners and indoor air quality
remediation companies in the months and years following initial
installation and commissioning.
Each year furnace and air
conditioner manufacturers deliver thousands of heating, vent
and/or air conditioning units to their distributors and contractors
for new installs and replacements. They build a range of capacities
and sizes to handle a variety of heating fuels in a variety
of ambient conditions from Alaska to Quebec to Florida. Energy
smart designs reflect the desire for quiet, heated or cooled,
comfortable air for breathing. Did we mention clean?
Oh yes. There is an air
cleaner. It is, invariably, a 1" thick panel filter loosely
installed into the 1" slide rail. The 2 most popular sizes
are 20"X25"X1" or 16"X25"X1". A colleague once
shared with me why they are called furnace filters; "Simply
put; these filters are efficient at stopping particles the
size of a furnace. |
Welcome
to the Unseen World of Micrometers |
| The lack of understanding,
indeed concern for what role filtration plays in providing
indoor air health in homes, schools and work places is rooted
in one solitary piece of flawed thinking;
"What
you cannot see cannot hurt you."
In fact, what you can see,
at the optic threshold, is a particle larger than 10 microns*
in size. Even a particle that size needs a sharp eye and
a bright beam of light to be seen. This might explain why
little more than 1" flat panel filters dominate the
air filters supplied with new home furnaces and air conditioners.
Unseen to this naked
eye are billions of smaller particles that blow right through
these furnaces and into homes and workplaces. These particles
mass over time and become part of our world. They can be annoying,
irritating, infectious and, to some people, quite toxic. With
only a 1" depth access rail provided for a flat panel filter
the long suffering consumer has only one place to turn for
relief…
And that place is, naturally,
the local home hardware store. There you will be dazzled by
point of sale marketing sleeves on more 1" panel filters.
There you can browse through a maze of products that work
mostly in the mind and word smithing of marketers who know
only too well that people suffering with allergies and other
respiratory problems will pay dearly for a breath of clean
air.
The hottest item on the
shelf is a passive electrostatic air filter that claims to
stop up to 95% of allergy causing pollen, dust, smoke, dander,
flies, mites, hair, lint, loam, bacteria, viruses, mold and
fungi down to 0.1 microns and they have ASHRAE* * testing
to prove it. If consumers could visualize how really small
a 0.1 micron particle is and how many thousands of these particles
occupy a moment's breath they would soon marvel at the mystical
electrostatic powers claimed by the manufacturer's literature.
Our testing using laser based particle counters and sophisticated
flow rate instruments raises serious doubts about many of
these claims especially with respect to allergen, size particles
and resistance to air flow for a clean filter.
Consumers should research the full
story about what contaminants are in the indoor air, their size
and concentration and the technologies available to treat and
remove them. Of course we know that this is not likely to happen.
"I don't want to own a filter factory. I just want a filter
that works in my home or office." So the responsibility
lies with us-the experts. |
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What
about that 1" slide rail filter access?
Why not provide a 2" or 4" track? More media area
usually means better performance and longer life.
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Why not provide an
access door on the filter plenum to prevent chronic by-pass
around the filter frame?
An integral filter holding sleeve or channel can
be field designed and installed. Low cost self-adhering
neoprene gaskets work wonders. Duct tape also works.
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Why not specify a
quality commercial/industrial treated filter media just
like the big buildings use?
There are quality filtering materials out there.
They are not expensive and they actually last a lot
longer than a 1" filter without significant reduction
in airflows.
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Up to 95% arrestance
efficiency on what? Smoke? Bacteria? Mould? Lint? Mites?
Dander? All, some or none of the above?
You need to understand the basis for performance
claims.
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Can you really stop
0.1 micrometer particles with a passive electrostatic
filter or any flat panel filter?
This is the same target particle that needs to be
controlled in Nuclear environments.
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How many particles
can be found in the unseen world inside?
Assume that your furnace or air conditioner operated
12 hours per day (more or less) and the flat panel
filter sees 1000 cubic feet of air every minute of
that time and each cubic foot of air contains 200,000
particles*, 0.3 microns and larger (that's
on a good day).
1000 cubic feet of air X 200,000 particles X 60 minutes
X 12 hours X 365 days = 52,560,000,000,000 particles.
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| We, the purveyors, designers, and manufacturers
need to better understand air filtration dynamics and the
simple facts about small particles and how they affect human
health and safety. This information is out there. NSF International
writes standards for and certifies legions of filter integrity
technicians. We can deliver air for critical care medical
and bio-hazard environments at efficiencies of 99.99% on 0.3
micron size particles. We need to apply some of this wisdom
to the ventilation appliances we deliver to homes, schools
and the workplace. While it may not always be practical to
install a H.E.P.A. filter with 200 square feet of filtering
media capable of stopping everything but dirty thoughts, we
can surely do better than a 1" flat panel or a 1" pleated
throwaway.
As you deliberate
on the root causes of poor indoor air quality and search for
lasting solutions, take a very close look at the design, installation,
accessibility and performance of the filtration system. This
often overlooked, maligned and least understood strategy may
be the key to better indoor air health. |
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Darrel Sutton has devoted the last 30
years finding lasting solutions to indoor air health problems.
He has spent all of this time with the same company, B.G.E.
Service & Supply, emerging through service, sales, management
and has owned the business for the past 18 years.
Today B.G.E. is a Canadian supplier of specialized
filtration products and services essential to the protection
of indoor environments. Darrel holds U.S. and Canadian patents
on a series of high efficiency filters widely used in schools,
hospitals and industrial environments throughout Western Canada.
His company employs 110 staff in manufacturing, sales and
service.
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B.G.E. has a storied history of service to the Indoor
Air Quality industry. In 1987 Mr. Sutton launched
the clean room and Bio-safety Cabinet Certification
service division known as BioLab. BioLab provides
integrity testing for a wide variety of applications
from negative air units in the asbestos abatement
industry to the operating suites at the W.C. McKenzie
Health Sciences Centre in Edmonton. BioLab also performs
I.A.Q. testing and remediation. Biolab technicians
are trained and accredited to the rigorous NSF Standard
for biological containment cabinets.
Born and raised on a farm near St. Paul, Alberta,
Canada, Darrel and his wife Dorothy live in Sherwood
Park, Alberta along with their 2 daughters, Kelly
and Roberta. Both have been very active in the sport
of curling. Darrel is a former Canadian Brier Champion
and is a past president of the Northern Alberta Curling
Association. In recent months you could find them
testing the air quality in the Gulf Islands as they
have become avid cruising sailors.
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If you have any questions or issues related to the
article published herein, you are welcome to contact
Mr. Sutton at: darrelsutton@thefiltershop.com
or continue
on to Clean Air Clinic presentation.
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