Dry air can lead to a host of problems especially for allergy and
asthma sufferers. Dry climates, winter air, and artificial heat all
contribute to the discomfort caused by dry skin, dry throats, and
irritated noses (which can lead to sinusitis). Winter is an especially
bad time for dry air. Home heating systems, especially forced-air
systems, often reduce the amount of moisture in the air which leads to a
home environment that is dry. The Mayo Clinic suggests several steps for
combating the effects of dry air:
provide a great environmental solution to the problem of dry air. Check out the next section of this article
to see how humidifiers work in your home.
- Drink more fluids. Water, juice, low-fat milk, and other
caffeine-free drinks all help your body to counteract the effect of dry
surroundings. Soups and broths are also a good choice, and they will help
keep you warm.
- Shorter showers and baths in warm rather than hot water are easier on
your skin. Mild soap is best. Showering less frequently will also help
guard against excessively dry skin.
- Moisturizing after showers or baths also goes a long way to help
prevent dry skin. Apply Vanicream lotion while your
skin is still slightly damp to help your body
absorb the moisturizer and increase its effectiveness. Use lip balm to
prevent or soothe chapped lips.
- Nasal irrigation, which
is safe to perform regularly, helps to combat dry nasal
Dry air doesn't only affect the people who live in the home. Dry
air can also damage furniture, wood floors, and paint in your home. A
humidifier not only helps those in your home breathe better, but it also
helps maintain the air in your home at a comfortable level for everything
inside it. Furthermore, air that's too dry makes the temperature feel
colder than it actually is. Humidification works in conjunction with
heating devices to keep you snug and warm during the winter and they save you
money on your heating bills.
How Humidifiers Work
There are so many types of humidifiers out there that a decision about
which humidifier to purchase can be overwhelming. As when purchasing any
appliance, it's helpful to learn how a humidifier works and what's
involved in the differences between them.
Humidifiers do what their name suggests - they add moisture to the air. Some
homes are equipped with humidifiers that are connected to their overall HVAC
systems, but portable humidifiers are most popular and extremely effective.
Here is a breakdown of the overall types of humidifiers with their advantages and disadvantages:
- Steam or
Warm Mist Humidifiers: These humidifiers boil water and
then release the steam into the air of the room. The technology is
simple, and steam humidifiers are the least expensive types. Inhalant
medications may also be added to this type of humidifier for those
suffering from coughing. The drawbacks of steam humidifiers, however,
are that they incur higher energy costs than other types of humidifiers,
and that the hot steam could be a hazard to young children.
- Ultrasonic Humidifiers: A vibrating disk operating at an ultrasonic
frequency creates water droplets that are then released into the air. The
fog that an ultrasonic humidifier produces is cool. Although energy costs
for running ultrasonic humidifiers is low, there are still two possible
disadvantages related to them - mineral dust caused by using water with a
lot of minerals in it and the presence of stagnant water that can breed
bacteria. However, there are ways to counteract these disadvantages.
(See suggestions in the next section.)
- Impeller Humidifiers: Like ultrasonic humidifiers, impeller
humidifiers are a type of cool mist humidifier.
A rotating disc throws water into a
diffuser which breaks the water into tiny droplets that then float into
the air. Like the ultrasonic variety, impeller humidifiers are subject to
the same concerns of mineral dust and bacteria.
- Wick/Evaporative Humidifiers: In this type of cool mist humidifier, some type of wick
(made of paper, cloth, or foam) draws water from a reservoir filled with
water. A fan that blows above the wick helps the surrounding air absorb
the moisture from the wick. Hence, this system is self-regulating because
a higher humidity means less absorption and vice versa. The fan in these
humidifiers can be loud, however, and, again, stagnant water poses a
See our Humidifier Buying Guide for more information about
different types of humidifiers.
As demonstrated above, choosing the right humidifier can be a tricky
business. The good news is that the potential concerns raised by some
types of humidifiers can be easily addressed. For instance, although
humidifiers with water reservoirs can breed bacteria and then release it
into the air in airborne form, adequate knowledge about your humidifying
unit coupled with proper maintenance prevents this from happening.
To guard against both bacteria and mold, some units boil their water
before they release it into the air (as in steam humidifiers and warm
mist humidifiers). Other humidifying units have added features such as a
UV light or a Hydro Stick. Our Enviracaire Humidifiers features a dual germicidal process
that has a UV component and a second water chamber that boils the water just before mist is released into the air. The
Enviracaire EWM-211D employs a UV bulb with warmed water, while the
Air-O-Swiss 2055 Air Washer use the Hydro Stick to eliminate bacteria and viruses.
The Air-O-Swiss 7135 Ultrasonic, AOS 7133 and
also use the Hydro Stick, as well
as heated water to destroy microbes. In addition, the ultrasonic
vibrations of many of the Air-O-Swiss humidifiers destroy much of the bacteria.
Guardian Ultrasonic Humidifiers use Silver Clean technology to fight
bacteria and mold from forming in the water tank.
Mineral dust is another possible concern. When water with a high
mineral content is used in a humidifier, the minerals are released into
the air and settle on surrounding surfaces, forming a white dust, or they
are inhaled. Using distilled water in your humidifier prevents this. In
addition, some humidifiers, like most Air-O-Swiss humidifiers,
have demineralization cartridges to help against white
No matter what type of humidifier you choose, even if it has several
built-in microbial features in place, it is very important that the unit
be cleaned regularly. Be sure to read the cleaning instructions that come
with your humidifier and follow them diligently.
Save Money on Heating Bills with Humidification
Keeping your home's humidity at ideal levels will also help you feel warmer. Low humidity makes the air feel colder because the warmer the air is, the more water it can hold; put another way, the more water in the air, the warmer the air feels. This phenomenon can be understood by considering how high levels of humidity in the summer make it feel hotter than it actually is: when the air is saturated with moisture, the sweat on our bodies does not evaporate, making us sticky and uncomfortable. But winter's low humidity has the opposite effect - dry air causes moisture to evaporate from our skin and we feel cooler.
By making sure that humidity levels are high enough we slow down our bodies' cooling mechanism, which we obviously don't need in the cold winter time. The upshot of all this is that a humidifier can save you a lot on your heating bills. Naturally, if you feel warmer even if the temperature remains the same, you won't be tempted to turn up the heat.
How Much Humidification Is Too Much?
Besides making sure that the moisture from your humidifier is pure and
clean, it's also important to maintain a proper level of humidity in your
home. While dry air is definitely uncomfortable and can lead to
discomfort, too much moisture in the air leads to another set of
problems: mold and dust mites thrive in overly moist environments, so
improperly maintained levels of humidity could cause further irritation
to allergy and asthma sufferers.
To keep your home environment comfortably humid without encouraging
dust mite and mold growth, experts recommend indoor humidity levels
between 40% and 50% for allergy sufferers. Some humidifiers, like the Air-O-Swiss 7135
Ultrasonic Antimicrobial Humidifier, come with a built-in hygrometer
or humidity gauge. If you have another type of unit, a humidity gauge like
Digital Humidity Gauge helps keep humidity levels within range. This
humidity gauge also features a clock, light, and digital thermometer, and
is useful in determining which areas of the home need humidification
during dry seasons and dehumidification during wet seasons. The Germ Guardian
Ultrasonic Digital Humidifier has a digitally adjustable spray function and
timer that allow you to adjust the percentage of vapor.
Humidity levels in the home are an important component of relieving
allergy and asthma systems through environmental control. Especially
during the winter, when dry air tends to be more of a problem, asthma and
allergy sufferers can greatly benefit from environmental control of
indoor humidity levels. Humidifiers make this possible.
Originally published in the
January 2008 issue of
Allergy Consumer Report
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