The ideal humidity level in your home is in the range of 30-50%. A too humid environment will also aggravate existing conditions such as asthma or eczema and can trigger numerous allergies. These high levels can also lead to the growth of fungus and mould and dust mites. 

Too low humidity can lead to dry skin and chapped lips, and it also can inflame your respiratory tract and make you more susceptible to colds and flu.   

Formaldehyde is used in many household products, such as particleboard, plywood, and fibreboard. 

Volatile organic compounds (VOCs) are chemicals that can be emitted as vapours from different types of common household products such as paint, candles and produced during cooking and cleaning. Exposure could also lead to eye, nose & throat irritation and even headaches. Breathing in low levels of VOCs for long periods may increase some people’s risk of health problems.   

The temperature in your home can also affect your health and comfort. The recommended temperature is 19-21°C. If the temperature is very high between 24-27°C, this is too warm, especially for young children. Also, if your home’s temperature is in the range of 13-15°C, this is too cold it can affect your resistance to respiratory diseases. 

In order to improve the indoor air quality of your home, identifying the source of the pollution and eliminating it is paramount.

Excess moisture is one of the most important and least recognized indoor pollutants, affecting both human well-being and building health. Excess moisture stems from warm air encountering cool air such as mirrors or windows. Where moisture collects, so do mould, mildew, and dust which can lead to allergies and asthma. High indoor humidity can facilitate an “off-gassing” of toxins in furniture and cleaning products.

Radon is another harmful pollutant that is a radioactive gas that is generated naturally in the soil and enters households from the ground.

Indoor sources of pollution stem greatly from combustion sources, namely tobacco, wood, coal heating, cooking appliances, and fireplaces which release harmful byproducts such as carbon monoxide directly into the indoor environment. Not to mention cleaning supplies, candles, paints, and insecticides that introduce many other dangerous chemicals into the indoor air. Improving your IAQ involves making some adjustments on what to bring into your home. Sources of air pollutants such as those that contain asbestos can be sealed or enclosed, subsequently, gas stoves can be adjusted to decrease the emissions. This manner of source control can be greatly cost-efficient.

Increasing the amount of outdoor air entering your home is another effective way of lowering the concentrations and emissions of indoor air pollutants.

From basic measures such as opening windows, doors, operating windows or attic fans, running a window air conditioner with the vent open increases the outdoor ventilation rate. Bathroom and kitchen fans directly remove pollutants from the room in which the fan is located and increases the rate of outdoor air ventilation. Not to mention through mechanical means and through infiltration, a process by which air enters the home through cracks and openings in walls and ceilings.

Ventilation can help improve control of indoor temperatures as well as help remove or dilute indoor pollutants that are airborne originating from indoor sources. This reduces the level of contaminants and improves IAQ.

Air cleaners range from relatively inexpensive table-top models to elite and expensive whole-house systems. Few air cleaners are successful in particle removal, while others are much less so. Essentially, air cleaners are usually not designed to reduce and remove gaseous pollutants.

For an air cleaner to be effective it would depend on how well it collects pollutants from indoor air and how much air it is able to draw through the cleaning/filtering element. Another important factor determining its effectiveness is the strength of the pollutant source, for instance, table-top cleaner is less likely to remove large amounts of pollutants from strong sources.

In recent years there has been notable publicity on houseplants, suggesting that they have been shown to reduce levels of some chemicals in laboratories. However, there is no significant evidence that houseplants are able to remove large quantities of pollutants.