Outdoor air pollution not only exacerbates asthma but also may...

- Environmental Health Perspectives, Vol. 118, No. 2, February 2010


What causes asthma & what exacerbates the symptoms of asthma?

Much research points to environmental triggers in the air. The air we breathe contains pollutants or contaminants that can trigger the symptoms of respiratory distress. There does not seem to be any scientific evidence as to what contaminants are more intrusive than others. Every person is different and seems to react differently to different contaminants. Generally, these can be categorized into particulates and gases that float around in the air and get ingested into the lungs when breathing. Particles can be as large as pieces of lint from clothing that are visible to the naked eye, or as small as microscopic pieces of animal dander less than 0.1 micron in size (a micron is a millionth of a meter).

effect of HEPAirX on IAQ

These smaller particles, often called ultra-fines, drift around in the air for hours and are easily stirred up with minimum amount of activity. Sources of large particles are clothing, animal and human hair, dust and dirt. Sources of smaller particles are from cooking, sneezing, animal and human skin flakes and dandruff, abrasion of surfaces, and handling of paper and paper products. Most of the larger particles will precipitate out of the air over time or will be caught in the nose or mouth when ingested.

The smaller particles, however, will pass right through the nose or mouth and enter the lungs. The smallest of these particles are even suspected of passing through the lungs directly into the bloodstream.

The second category of contaminants is gaseous compounds found in the inside and outside air. Some are specific compounds such as carbon dioxide (CO2) and carbon monoxide (CO), while others fall into the generic category of volatile organic compounds (VOCs). These are mostly by-products of chemicals used in fuels and building materials. For example, formaldehyde is used in the manufacturing of many building components. Over time, this gas then is released (or out-gases) from these materials and becomes mixed with the room air. Many building materials such as plastics, wood, paints, etc., release these VOCs in a room. A computer, for example, contains hundreds of components that are made from organic compounds and will continuously release these gases over time.

HEPAir X100 was designed to not only remove or reduce the quantity of particulates in the air but also the concentrations of gases.

By recommending the use of the HEPAir X100 system in the bedroom, we increase its effectiveness at removing contaminants from a smaller space but also increasing the time the occupant is exposed to clean air, which on the average is about 40% of that person’s day.

What makes HEPAir X100 different from other room air cleaners on the market?

HEPAirX is the only recirculating room air cleaner that has a built-in ventilation system that brings fresh, outside air into the bedroom. And HEPAirX is the only cleaner that both heats, cools, and dehumidifies the room.

Why is it important to have built-in ventilation, heating and cooling?

Because it allows the room to be isolated from the rest of the building. This prevents the central HVAC system from continuously re-contaminating the bedroom air with pollutants. By isolating the room and providing a slight positive pressure, air quality can be controlled by the re-circulating airflow through the HEPA filter.

What are some other differences between HEPAir X100 and other room cleaners?

  1. The amount of airflow handled by the unit – most filter units only circulate small amounts of air and primarily at the floor level. The HEPAirX has an airflow rate of 200 cubic feet/minute, which is the equivalent of completely changing the air in the average sized bedroom of 1,000 cubic feet over 12 times per hour.
  2. The built-in, air-to-air heat exchanger to capture the energy in the exhaust air to pre-condition the incoming outside air.
  3. The high-velocity adjustable discharge nozzles on the unit to allow the occupant to aim the air for maximum distribution in rooms of various sizes and configurations.
  4. The HEPAirX relies on the use of natural fresh outside air to remove and reduce the concentration of gaseous pollutants and not on artificial means such as UV light or charcoal filters, which require frequent replacement.

Where do contaminants come from?

Virtually, everywhere we look inside and outside the home – from our own bodies to the plants and furnishings around us. Every time we move we generate particles from our feet stirring up dust and dirt on the floor, from our clothing, from the dandruff on our heads to the skin flakes we naturally shed every second. Outside particles are generated from plants, trees, shrubs, from auto and diesel exhaust, from the friction of tires on road surfaces – and the list goes on. Inside particles are generated from our pets, from cooking activities, fireplaces and wood stoves, and from carpeting. Volatile organic compounds are generated by outgassing from plastics, computers, video games, carpeting, furniture, cleaning compounds, and TVs.

How does the dust and dirt from outside get into a house if the windows and doors are kept shut?

All houses, no matter how tightly they are constructed, have small cracks and crevices through which particles and fumes can enter. This is made worse by the negative pressure that is being created by exhaust fans in bathrooms and kitchens.

How do houses develop negative internal pressures?

Primarily from exhaust fans and exhaust flues from fireplaces and furnaces. Most building codes require exhaust fans over the cooking stove to exhaust the fumes. Also, exhaust fans are required in bathrooms without an outside window. And every fireplace and furnace has to be exhausted to the outside to remove the toxic fumes.

Do you recommend removing carpeting, changing bed linens, removing stuffed animals and electronic games or TVs from the bedroom?

All of these would be helpful at reducing the amount of contaminants in a room, but not at the risk of stressing the occupant. Particularly if it is a child’s bedroom, the most important thing is for the child to get a good night’s sleep; items that are familiar to the child allow him/her to feel more secure and comfortable. However, we do recommend that the bedroom door be kept closed to reduce the infiltration of contaminants from the rest of the house, and the outlet grilles from the HVAC should be kept closed or taped shut. Also, pets should be kept out of the child's room during the night.

What if the occupant is not sensitized to airborne contaminants such as particles or “volatile organic compounds” (VOCs)?

Every person is different and is sensitive to various pollutants, or in various degrees,  not all of which are reduced or eliminated by the HEPAirX system.

Why only one room? Why can’t we treat the whole house?

The objective is to reduce the occupant’s exposure to contaminants in the air that may affect the frequency and severity of the condition. By exposure, we not only mean the amount of contaminants in the air at any one time but also the length of time the person is exposed to them.

Why does HEPAir X100 have a window sleeve?

Because the unit is designed to operate year-round, and the opening needs to be sealed better than a typical window air conditioner which is only used seasonally. This reduces the heat loss and improves energy efficiency.

Does HEPAir X100 control humidity?

HEPAir X100 does not directly control humidity but does dehumidify. Warm, moist air is the leading cause of mold and mildew, and it creates an environment that supports the growth of many organisms such as dust mites and bedbugs. When running in the air conditioning mode, the HEPAir X100 continuously removes moisture from the air, both cooling and dehumidifying the room. The HEPAir X100 is one of the only air cleaners that displays the relative humidity in the room at all times.

What if I have a forced hot air heating and/or cooling system in our house?

These air handling systems must be shut off into the bedroom. This is easily accomplished by taping over the registers into and out of the room. The HEPAir X100 will now take over complete temperature control of the bedroom, heating, cooling and dehumidifying.

What if I have a hot water or electric heating system in the house? Do we have to shut it off in the bedroom?

No, because these do not bring in contaminated air from the rest of the house. The HEPAir X100 unit senses the temperature in the room and will not add heat if not needed. If your central system has a night setback for the rest of the house, the HEPAir X100 will continue to maintain the room temperature by using its own internal heating coil.

Why do we need to isolate the room from the rest of the house?

Isolation is an important strategy in maintaining the air cleanliness of the room. Contaminants are generated all over the house, from cleaning and cooking activities to running electronic appliances. If the room is not isolated from the rest of the house, the contaminants in the rest of the house will continuously re-contaminate the bedroom. This is especially true with a forced air heating system, which literally turns over the air in the bedroom replacing it with new contaminated air. Because of cost, energy, size and noise considerations, the HEPAir X100 unit is not designed to overcome all this recurring contamination. It is designed to quickly clean up the air in the room and then maintain it at extremely low contaminant levels when running.