Understanding relative humidity is essential for the safety of your home. A humidifier is a great appliance for comfortable living, but you need to know how to safely operate it. Dry air can damage your body and household items, moist air is also a problem. In climates where moist air is a problem, dehumidifiers have been introduced.

What relative humidity level should you use? The rule of thumb is 30-50%.

Your humidifier may come with some sort of humidity meter. If you cannot find one specifically for your model of humidifier, check out your local hardware store for a hygrometer.

When the air is too dry:

During winter, when the heat is on, the relative humidity in your house can become very low. This is because heated air can hold much more moisture than cold air. So, as the air in your home heats up, it becomes “thirsty” and begins sucking moisture out of surrounding surfaces: plants, walls, furniture, books, paintings, human bodies, everything. Whenever we heat air we dry out the air to uncomfortable and damaging levels.

By keeping the humidity above 30%, you can normally turn down your thermostat a few notches. Your heated air will feel warmer, creating a safer, more efficient environment.

When the air is too wet:

The reason to use a humidifier is simple. The reason to keep the humidity under 50% is not so obvious.

Dust mites, the culprits behind allergies, love moist air. When the relative humidity of a home climbs above 50%, dust mites begin rapidly multiplying. This can cause allergic reactions in sensitive people.

Mites aren’t the only unwelcome guests that can infest your home. Fungi and mold become prevalent when the relative humidity of a home reaches 75%. Fungi and molds can cause asthma attacks and rhinitis (inflammation of mucous membranes of the nose) in some people.

You should also reduce setting if moisture forms on windows, walls etc, or if there is dampness around the area of your humidifier. Keep in mind that you don’t need to be concerned it this temporarily happens due to cooking, showering, etc.

Summing up:

If you get nothing more out of this article, make sure to remember that the humidity levels of your house need to be within the 30-50% humidity bracket. Regulate your humidity with your humidifier’s built in humidity meter or by a hygrometer from any good hardware store.

Generally, any tricks and tips that apply to keeping heat in, will most likely improve the performance of a humidifier. The performance of your humidifier can be improved by:

• Sealing doors and windows, and fireplaces that are not in use.
• Use tape or special window and door sealers.
• Do not keep your humidifier in a confined space, get the most out of your humidifier by making sure it is not being restricted by it’s surroundings.

NB: Do not humidify over 50%, also reduce setting if moisture forms on windows, walls etc, or if there is dampness around the area of the humidifier. Recommended humidity levels are between 30-50%, this will vary on your personal comfort and the type of humidifier you own. Read understanding humidity for more information of recommended humidity levels.

Humidifiers come in all shapes and sizes, from hatbox-sized portable units to furniture-sized consoles. But they all do the same thing: They put moisture in the air. And they do it in one of five ways.

1. Evaporation: Evaporative units have a fan inside them that blows air through a wet pad, and this moisture-laden air then continues on into the room. (“Wicking” humidifiers do the same thing, only the air is blown through a moisturized filter instead of a pad.) Evaporative units don’t produce a spray and are therefore less likely to spread germs than are units that throw a cool mist into the air. The wet pads however, can become a breeding ground for bacteria if not cleaned regularly.
2. Steam:These units, sometimes called vaporizers, boil water and send it into the air as steam. They tend not to put microorganisms into the air; after all, it would take an extraordinarily tough germ to survive the boiling process. Unlike other kinds of humidifiers, they produce little or no “white dust.” Steam units leave the minerals behind when they boil water in their tanks.
3. Warm mist:These units boil water just like steam vaporizers, only the steam is cooled slightly before exiting the unit, resulting in a “mist” of warm water droplets instead of real steam.
4. Cool mist:These units break up water into tiny droplets and spray a cool mist into the air. Because the water isn’t boiled, the cool vapor may contain potentially harmful organisms if the tank is not properly cleaned and sanitized.
5. Ultrasonic:These units use high-frequency vibrations to break up water droplets into an extremely fine mist. The mist produced by these machines contains no molds and comparatively few live bacteria. It is thought that the ultrasonic vibrations may “break up” and shatter living organisms along with the water droplets. However, while these bits of dead microbes may not cause respiratory infections, they may still trigger allergic reactions in sensitive people.