Air Con: Filtering Air Pollution For Better Breathing

Air conditioners are designed to provide comfort by replacing warm air with cooler air. While some ACs come with air filters, they cannot make the air totally pollutant-free. Ionisation filters, for example, can remove some smoke, dust, mould spores, odours, allergens, and germs, but they cannot clean smaller particles that are invisible to the naked eye. Similarly, electrostatic filters can trap contaminants and particulate matter, but the trapped particles can be freed and re-enter the atmosphere. Wall-mounted air conditioners do not bring in outdoor air pollution, but some central air systems do.

Air conditioners do not bring in outdoor air pollution

Regular wall-mounted air conditioners have a unit outside connected to the inside by tubes. However, these tubes are circulating coolant, not bringing in outside air. The air conditioner takes air from the top, runs it over cooling coils, and blows it out the front.

Tests have been carried out to check the air quality of the air coming out of an AC unit, and the results show that it is no different from the ambient room air. Even on very dirty days, the air coming out of the AC is nowhere near as polluted as the outside air.

While air conditioners do filter air, they are not a replacement for a dedicated air purifier. They have limitations and do not actively improve indoor air quality. In fact, air conditioners can worsen indoor air quality by circulating stale and polluted indoor air without purifying it. This can lead to symptoms such as nasal issues, itchy eyes, headaches, dizziness, and fatigue.

Ionisation filters in ACs

Air ionisers are devices that use high voltage to ionise, or electrically charge, air molecules. Negative ions, or anions, are particles with one or more extra electrons, resulting in a net negative charge. Positive ions, or cations, are particles missing one or more electrons, resulting in a net positive charge. Ionisation filters in ACs work by releasing ions, which disinfect and diminish bad smells in the room. They also gather house dust, pollen, and other small particles that are responsible for allergies.

The use of ionisation filters in ACs has been found to have beneficial health effects. For example, the National Health Service (NHS) in the UK found that the installation of a negative air ioniser eliminated repeated airborne acinetobacter infections in a ward. Additionally, positive and negative ions produced by air conditioning systems have been found to inactivate viruses, including influenza.

However, it is important to note that ionisation filters in ACs may not be as effective as other types of air filters, such as High-Efficiency Particulate Air (HEPA) filters, which are commonly used in hospitals and have a good track record of reducing viral infections. According to Consumer Reports, a non-profit U.S.-based product-testing magazine, air ionisers do not perform as well as conventional HEPA filters in terms of their clean air delivery rate (CADR).

Furthermore, while ionisation filters can help to remove larger particles from the air, they may not be effective at removing smaller particles that can cause chronic breathing problems. Additionally, as air conditioners contain moisture, they can accumulate mould, which can trigger respiratory issues such as Chronic Obstructive Pulmonary Disorder (COPD). Therefore, while ionisation filters in ACs can be beneficial, they should be used in conjunction with other air purification methods to ensure effective air pollution control.

Air purifiers vs ACs

While air conditioners and air purifiers share some similarities, such as fans, filters, and vents, their primary purposes differ. Air conditioners are designed to cool the air and maintain a specific indoor temperature. On the other hand, air purifiers are meant to improve indoor air quality by removing contaminants and pollutants.

Air conditioners are essential for keeping your home or office space cool and comfortable, especially during hot summer months. They achieve this by replacing warm air with cooler air. However, they do not effectively remove indoor air pollution. Regular maintenance of air conditioners is crucial to prevent the buildup of mould and other contaminants that can negatively affect indoor air quality.

Air purifiers, on the other hand, are specifically designed to enhance indoor air quality. They achieve this by capturing and removing various airborne particles and pollutants, such as dust, allergens, smoke, bacteria, and odours. Air purifiers can be equipped with different types of filters, such as HEPA filters, carbon filters, or ionizers, each with its own unique capabilities and limitations. For example, HEPA filters are highly effective at capturing small particles, while carbon filters excel at capturing gaseous pollutants.

One key distinction between air conditioners and air purifiers is their impact on energy consumption. Air purifiers generally consume less energy than air conditioners, which can result in significant cost savings over time. Additionally, air purifiers offer flexibility in terms of portability and placement, as they can be easily moved between rooms.

While air conditioners are not designed for deep air purification, some manufacturers combine air conditioners with air filters to improve their air-cleaning capabilities. However, even with air filters, air conditioners cannot achieve complete air purification. Air filters can become clogged with trapped particles, reducing airflow and potentially reintroducing pollutants into the indoor air if not cleaned or replaced regularly.

In summary, air conditioners are primarily designed for temperature control and comfort, while air purifiers focus on improving indoor air quality by effectively capturing and removing various types of airborne contaminants. Combining an air conditioner with a separate air purifier can be an ideal solution for maintaining a comfortable and clean indoor environment.

Air conditioners and health risks

Air conditioning systems are designed to keep our homes and offices comfortable during hot summers or cold winters. However, they can also be a source of health risks if not properly maintained. Here are some of the potential health risks associated with air conditioners:

Indoor Air Pollution

Air conditioners can sometimes contribute to indoor air pollution instead of reducing it. Clogged ductwork, dirty filters, a broken condenser, and poor maintenance can cause an air conditioning system to blow out bacteria, mould, and other pollutants into the air. These substances can be harmful to our health and well-being. For example, dirty filters may allow pesticides, pollen, and other outdoor pollutants to enter our homes. Additionally, the cooling system can remove particulates from the air and then circulate them back into the room, potentially triggering allergies or respiratory issues.

Bacterial and Airborne Diseases

The moisture in air conditioners can also provide an ideal environment for moulds and bacteria to grow. This can lead to the spread of bacterial diseases and trigger respiratory issues such as Chronic Obstructive Pulmonary Disorder (COPD). Legionnaire's disease, an infectious and potentially fatal form of pneumonia, has been associated with contaminated air conditioning systems.

Chronic Headaches and Fatigue

Some people who work in centrally air-conditioned environments report experiencing chronic headaches and fatigue. This is believed to be caused by cold air blocking nasal passages or mucus membranes, leading to mucus irritation and breathing problems.

Temperature Sensitivity

Constant exposure to air conditioning can make individuals intolerant of hot summer weather. The body acclimates to the cool temperatures, and when the air conditioning is turned off, the higher temperatures can become uncomfortable or even harmful.

Environmental Impact

While not a direct health risk, the environmental impact of air conditioning systems is significant. Air conditioners contribute to greenhouse warming, which has far-reaching consequences for the planet and, by extension, human health.

To mitigate these health risks, it is essential to properly maintain air conditioning systems, regularly change or clean filters, and ensure adequate ventilation in enclosed spaces. Combining air conditioning systems with air purifiers can also help improve indoor air quality.

Air conditioner filters and their effectiveness

While air conditioners are great for maintaining a comfortable temperature, they are not as effective at filtering air pollution. Air conditioners can even contribute to indoor air pollution due to the moisture they contain, which can accumulate mold and trigger respiratory issues.

Some air conditioners do have built-in filters, but these are not as effective as dedicated air purifiers. The air filters in air conditioners cannot clean smaller particles that are unnoticeable to the naked eye, which can result in chronic breathing problems.

There are various types of filters available, such as HEPA filters, which use a dense filter to remove particles, and UV filters, which use ultraviolet light to kill bacteria and viruses. Filters are rated using the MERV system, which stands for Minimum Efficiency Reporting Value, with higher numbers indicating a higher level of effectiveness. For example, a MERV rating of 8 to 13 can clean the air almost as effectively as a portable air purifier. However, thicker filters, which are generally more effective, may interfere with airflow into the HVAC system.

It is important to note that air filters need to be replaced regularly, as the particles they trap can be freed and re-enter the atmosphere. Homes with certain conditions, such as smoking, burning candles, or having pets, will need to replace their filters more frequently.

Frequently asked questions