Many people buy dehumidifiers to clear condensation from windows or damp and mould from walls. What often gets overlooked are the large health benefits that also come from maintaining your home within the ideal relative humidity range (40% to 60%RH). These benefits are particularly prominent for allergy and asthma sufferers, but maintaining a healthy humidity in your home is advantageous for everyone, be they the young, old, sick or your typical adult.
In this article we are going to look at what happens when the humidity in your home is too high, what problems can occur and then what to look for in a dehumidifier to solve these problems, with some of our recommendations for specific models.
Implications of High Humidity
The ‘ideal’ band for the relative humidity indoors is often stated to be 40% to 60%RH and this has a lot to do with the health benefits of living within such a range.
Bacteria and Viruses
Scientific studies have proven that the survival, growth and infection rates of bacteria and viruses are increased significantly by humidity above 60%. This is because these microbes are highly susceptible to drying-out and below roughly 60% humidity their structures change significantly, either killing or incapacitating them.
Moulds are omnipresent, so there’s no getting away from them. However, we all know that mould loves to grow in humid places (greater than 60%RH) in the corner of rooms and behind furniture. While mould spores are constantly around us, having a growing patch of mould in your home, however small, can dramatically increase the number of spores in the air and some moulds also produce mycotoxins, which are harmful to our health (source: pauldavis.ca/mould-remediation-services/).
You’re never going to be able to get rid of dust mites, however if the humidity in your home of over 60% to 70%RH then conditions are extremely favourable for their growth and reproduction. The American Academy of Allergy, Asthma and Immunology (AAAAI) have found that humidities below 50%RH greatly limit their growth.
Health Problems With High Humidity
Bacteria and Viruses
Studies have compared people working in offices with conditions of medium humidity to those working in offices with high humidity, looking at respiratory infection rates and absenteeism due to illness. They found that people working in conditions of higher humidity had significantly more respiratory infections and days off work for sickness.
When it comes to your health, it’s not the mould on the wall that is directly most damaging to your health, it’s the airborne mould spores (how mould spreads) and mycotoxins, harmful airborne toxic compounds that some moulds produce that are the problem.
Typical symptoms of mould exposure include:
- Sore, red, watery or irritated eyes
- Runny nose or sinus congestion
- A cough, sneezing fits, wheezing, a tight chest or difficulty breathing
- Skin rashes
I was shocked when I read this, but there is a correlation between mould exposure during an infant’s early years and the likelihood of them developing asthma or other respiratory issues later in life.
In people who have asthma and closely linked respiratory problems, mould exposure is almost certain to heighten symptoms, such as those listed above.
Opportunistic parasitic fungi thrive in conditions of high humidity. This means that conditions such as athletes foot and fungal nail infections become more likely and harder to combat when they have occurred.
Usually in individuals with a compromised immune system, such as the old and very young, more serious fungal infections can occur (known as mycosis).
Dead or alive mould particles and mycotoxins in the air are known allergens and in those who are sensitive to allergens they can cause an autoimmune response that results in an array of unpleasant symptoms, the same as those you see in hay-fever sufferers.
Dust mites can cause an allergenic autoimmune response of congestion, itchy, watery eyes and a wheezy dry cough in the same way that mould does. As humidity increases and the populations of dust mites get larger, the symptoms are only likely to get worse.
Dehumidifiers Can Improve Your Health
The right dehumidifier can benefit your health and allergies in three ways.
Reducing and Controlling Humidity
We’ve described above the damaging effects of high humidity. Equally, very low humidity can also be damaging to your health by drying things out too much. A dehumidifier is the only simple way to manage the humidity levels in your home, but you must be careful to buy one that is powerful enough to be able to actively control the humidity levels in your home, not simply extract moisture. Our dehumidifier comparison chart can guide you here.
While all dehumidifiers have a dust filter, that isn’t nearly fine enough to cut out any of the bad guys listed above. What you should look out for is an anti-bacterial filter(s), which should kill these microbes upon contact. The EcoAir DC202 has by far the best air filtration system currently available.
Ionisers work by negatively charging air particles. This causes these particles to clump together and fall out of the air or attach to surfaces where they can be removed through normal cleaning practices. They also kill microbes when they charge them. They have been proven to dramatically reduce the concentration of allergens in the air in hospital wards and offices. In addition, some studies show that an atmosphere with increased negative ions reduces our bodies histamine production, lessening many of the symptoms listed earlier in the article.
Some dehumidifiers, particularly desiccant dehumidifiers, come with ionisers built in. The most popular example at the moment is the EcoAir DD122FW Classic.
If your home is suffering from high humidity levels, remember that it’s not just your home and furnishing that is suffering, it’s also the health of you and of those around you. Our recommended dehumidifier for curing these issues is the EcoAir DC202, or if you’re on a tighter budget, the EcoAir DD122FW Classic.