Friday, October 3, 2008
Why You May Want Healthier Air at Home - and How to Get It
While we worry about smog, worse pollution is closer to home. In fact it is in our homes.
As reporter Chandra Shikhar discovered, “more than three decades after the Clean Air Act, the air outdoors is much cleaner … but indoor air is another matter.” “Pollutants inside buildings vastly outnumber those outside”, said Jed Waldman at the California Department of Health Services.
Yet there’s good news. You can take a few, powerfully simple steps to make the air inside your home – the one place you can control – better than the air outside. Here’s to living healthier and longer with clean air at home.
Five Alarming Facts to Motivate You to Act
1. 50 percent of all illnesses are either caused or aggravated by poor indoor air quality.
2. Asthma is now the most common chronic disorder in childhood, affecting an estimated 6.2 million children in the U.S., according to the American Lung Association.
3. The EPA ranks poor indoor air quality as one of top five public health risks. (Asthma, allergies, and other breathing difficulties, lung and heart disease, headaches and dizziness.)
4. Americans spend nearly 90% of their time indoors.
5. Indoor air pollution can be two to fives times to sometimes 100 times higher than outdoor air pollution.
Who is Most Vulnerable to Dirty Air?
Those most at risk to polluted air in their home:
• Infants and young children.
• People with asthma, allergies or other respiratory illnesses or who have heart or lung problems – especially those who also lead stressful lives.
• Elderly, most of whom have reduced lung capacity.
• Smokers and those who live with them.
• People who work at home.
• Those in colder climates who tend to stay inside even longer.
• People in urban areas.
• Those living in energy-efficient or other well-built homes that seal air inside.
Even Tidy, Conscientious People Get Sick From Their Home
Even if you use non-toxic products, clean regularly, have a HEPA vacuum cleaner and do not smoke, nor have asbestos or damp surfaces or use a fireplace or a wood stove, you are still vulnerable to the tiniest particles in your home – the respiratory suspended particulates (RSPs).
They become airborne from even slight actions such as walking on the carpet, sitting on a sofa or lifting a blanket. The particles are microbial air contaminants, ranging from bacteria and viruses to fungi and spores. They include pollens, spores, asbestos fibers, insect debris, food remnants, and pet dander.
What Makes RSPs So Dangerous?
Size does matter. RSPs are so small that you can breathe them deep into your lungs. Multiple studies show they cause acute or chronic health effects. They enter the blood or lymph tissue and cause a host of respiratory problems. Those who are allergic to respirable particles succumb to a range of health problems, from allergic rhinitis to bronchial asthma. Radon and benzo-a-pyrene (suspected carcinogenic agents) are transported by RSPs into the lungs.
Gases or other substances may also be carried by RSPs into the lungs. Respiratory illness, especially chronic illnesses like bronchitis, emphysema, and asthma may be linked to, or aggravated by, exposure to RSPs.
Lung damage may be small yet it is cumulative. That is especially devastating for young children as the effect of the damage increasingly reduces lung capacity as they age. Recent research shows that respiratory problems from RSPs and other air pollutants can also lead to heart problems.
It Gets Worse
These pollutants affect you more if you are sensitive to them or the longer you are exposed to them – for example, the amount of time you spend at home. Health dangers range from itchy eyes to allergic reactions to more dangerous effects such as a damaged immune systems, reduced lung capacity, heart difficulties and cancer. Slightly larger particles, such as pollen, dander and house-dust allergens, don't penetrate your lungs as deeply, but they can cause debilitating allergic responses.
Choose the Most Efficient Air Cleaner for Your Home
You can get a whole home air cleaner if you have a forced air system, meaning you have a furnace or furnace and air conditioner. Then you already have a basic mechanical filter. That’s your first, crude level of defense against air pollution.
These mechanical filters are typically made of a coarsely woven metal. They can only remove large particles of dirt and hair. Even that capacity is greatly reduced when the filters are not replaced regularly. Worse yet, these mechanical filters can’t capture the tiny RSPs. If you do not have a forced-air system or want to consider a portable, room-only device, here’s the basics you need to know.
Get a Portable Room-only Device or a Whole Home System?
The next step is to choose between a portable room-only cleaner and a whole home cleaner. Unfortunately, some don’t have that choice. You can’t get a whole home system if you do not have a forced-air home furnace or air conditioning system.
In considering portable devices you have two kinds: ones with mechanical filters or ionizers.
Mechanical Filter-Based Portable Air Devices
The best kind of portable systems meet the HEPA (high efficiency particulate air filters) standard. That means they can capture 99.97 percent of the airborne particles 0.3 microns and larger that pass through the filter. These include tobacco smoke, household dust and pollen. Mechanical filters draw air through a flat, pleated or high efficiency particulate air (HEPA) surface to trap particles.
That design means HEPA filters can be efficient in the beginning yet tend to clog easily. Clogging reduces airflow and thus their ability, over time, to remove pollutants. Filters must be changed with some frequency to maintain HEPA-level efficiency. Not all if us remain that diligent, even if we intend to be. “Gary McEldowney, the marketing director for AllergyBuyersClub.com, said the cost of a purifier could range from $150 to $700, depending on size and features. Replacement HEPA filters cost $40 to $150.” Other models are much more expensive.
Another obvious disadvantage is that a single room cleaner can’t keep the rest of the air in your home clean. It can’t even maintain the high HEPA standard in the room in which it is used, unless it runs continuously and the door and windows to the room are kept closed – an unlikely possibility.
Put simply, this room-only approach is akin putting a bandaid on a wound.
Portable Room Ionizers
Ionizers emit a small charge to the air stream that causes particles to adhere to the filter or other surfaces by a magnetic-like attraction. But this is not efficient as particles can become re-suspended.
Worse yet, ionizing emits ozone, a lung irritant that is also linked to other health problems. It can have damaging health effects, especially for those with asthma and other lung diseases, children and the elderly.
According to Consumer Reports and the EPA, “While some indoor air pollutant concentrations decline in the presence of ozone, other pollutants increase. In fact, upon reaction with ozone, some previously undetected, toxic chemicals emerge in indoor air, including formaldehyde and other aldehydes.” See the EPA’s article, "Ozone Generators Sold as Air Cleaners."
To add insult to injury, the units make a zapping and other noise as they emit ozone. Also it requires time-consuming cleaning and frequent filter changes to maintain even a lower level of performance.
Your best option, if you cannot get a whole home air cleaner, is to get a portable, room-only device with a mechanical, HEPA-grade filter. If your home has a forced-air system you can get a whole home system. Now you’ll see your options. The good news is that there are clear choices. You do not have to spend a lot of time nor money to get healthy air throughout your home.
How to Choose the Most Efficient Whole Home Air Cleaner
Whole home air cleaners can be placed in the ductwork of forced-air systems heating or air-conditioning (also known as in-duct air cleaners).
“If you are using forced air for, the best way to clean the air in your house is to add a filtration module to your system,” said Alex Wilson, president of BuildingGreen in Brattleboro, Vermont. As you’ll read further down, however, you may not have to mess with the ducts, with a hybrid system. It can be retrofitted, that is bolted right onto your existing unit.
Following are the categories of air cleaner systems, described in the order of increasing levels of air cleaning performance, maintenance needs and convenience.
Here are the kinds of whole home air cleaners from which you can choose:
1. Electrostatic Precipitators (ESPS)
All electrostatic precipitators use electricity to charge particles passing through them and then attract them electrically (make them “stick”) to either plates or a filter.
2. Electrostatic Filters
This is the least expensive kind of filtering system, removing 90% of particles that are 0.3 microns or less. It requires frequent filter change and, more importantly, performance goes down over time. One example is the Filtrete. Electrostatic units filter the air using static electricity. They have a static charge on the filter to allow airborne particles to "stick" to the filter, just like static-charged clothing sticks together. The drawbacks to these units are that they capture fewer RSP’s and the filter needs to be replaced frequently
3. Conventional Electronic Air Cleaners
EACs charge particles and cause them to stick to plates inside the unit or to a filter. In this way they trap and filter up to 98% of pollutants from the air passing through your heating and cooling system. This kind of air cleaner can capture microscopic impurities like dust, smoke and smog particles in addition to larger particles like mold spores and cat dander.
Collected pollutants are removed by cleaning the plates in the sink or dishwasher. Some EAC’s use grounded filters instead of plates but these require expensive replacements.
4. Hybrid Electronic Air Cleaner
A hybrid electronic air cleaner provides the upside of traditional EACs (high efficiency) without the downsides (reduction of efficiency over time, messier and more time-consuming maintenance, more complex installation, no ozone emitted and fewer, more frequent and time-consuming filter changes.)
Here’s how the newer hybrid, AspenAir Inside accomplishes this. It eliminates the need for wires (or pins) and plates. Instead it uses a non-metallic material to conduct the electricity and charge the RSP’s. This non-metallic design avoids the wear and tear and faster filter clogging that degrades performance over time.
All other EACs’ use of wires or pins cause a loss of up to 80% RSP collection efficiency within 60 days.
One final thought. Winter is coming. Days are getting colder and shorter. You may be spending more time inside. Consider installing an air cleaner soon. Healthier air is the priceless gift for yourself and those who share the holidays with you at home.