Humidifiers

A humidifier is a device that can be used to increase humidity, either in a single room or it can be attached to a HVAC system to cover the whole indoor environment.

What is pollen?

Pollen is powdery substance released from the flowers of plants and trees , for the purpose of fertilizing other plants.Pollen can be carried between plants via insects that feed on flower nectar, this type of pollen does not cause disease.The pollen that is airborne is significant in asthma, hay fever and allergy in general.

Why would we want to increase the humidity indoors ?

People with asthma and hay fever get attacks of the disease in days when the pollen concentration in the atmosphere is high. However, if the humidity is high enough, the pollen granules will become weight and therefore too heavy to float in the air, and this will decrease the amount of pollen that allergic people are exposed to.

What are unwanted effects of increasing humidity?

Higher humidity encourages the growth of mold and house dust mite, which in turn cause a lot of allergy problems. The solution is either to limit the humidification to one room(the bedroom of the person with hay fever or asthma ), or to take the necessary precautions for mold and dust mites with whole house humidification.That is why it is important to consult an allergist to identify the specific allergen causing the symptoms.

What are some types of humidifiers and how do they work ?

1. Evaporative humidifier: Consists of a “wick” through which water filters from a connected reservoir, the water then evaporates from the tip of the wick, aided by a fan that blows air from behind the wick outwards. 
   The rate of evaporation at the tip depends on the saturation of the air with water vapor (humidity), that is why this type is self regulating (it will only humidify the air to a certain degree then stop), and it is more effective in dry climate.Also contaminants are removed during the filtration of water through the wick.
   
2. Steam humidifier: The water is boiled and released as steam, it is energy consuming and there is the noise of boiling. However it is the cheapest types, and the boiling kills microbes.
   
3. Impeller humidifier: Water is thrown at a special device from a rotating tube, this causes drops of water to spread everywhere.The water does not need to be heated so this method is less energy consuming.There is no effect on contaminants in the water.
   
4. Ultrasonic humidifier: A sheet vibrates at ultrasonic speed, scattering the water on its surface in all directions.If the water is not clean, any microbes or suspended particles are spread in the air as well.