The importance of ventilation
Ventilation is the replacement of stale air indoors by introducing clean, fresh air in its place. While good ventilation is necessary to avoid feeling suffocated, it is also essential to ensure sufficient ventilation in every building for a variety of other reasons. Proper ventilation helps improve air quality: from a public health perspective, maintaining good air quality is critical in public spaces such as schools, supermarkets and malls, especially in the context of COVID-19. When indoor spaces are insufficiently ventilated, air builds up and the concentration of gases such as carbon dioxide increases. Accumulation of such gases and moisture indoors can be uncomfortable for occupants. When public spaces are insufficiently ventilated, respiratory particles can build up and be spread by people coughing and sneezing. Now we have seen why proper ventilation is so important, let’s see how we can achieve it!
How to achieve proper ventilation
Imagine clean air coming in from one end of your house and pushing out the stale air from the other end. This is called cross ventilation: the most natural and straightforward form of ventilation. Cross ventilation occurs due to the pressure difference between outdoors and indoors. The air is drawn into the low-pressure side from the high-pressure side. Cross ventilation is one of the most cost-effective ways to provide natural ventilation since it only requires that you open any windows and doors in the room. Ventilation can also be achieved by mechanical means such as exhaust fans and air conditioners, working on the same principle of a pressure difference between indoors and outdoors. A ‘mixed-mode’ ventilation can also be effective; in this case, both natural and mechanical ventilation strategies are used together. Modern buildings are equipped with heating, ventilation and air conditioning (HVAC) systems to regulate temperature, humidity, and air quality. However, many modern buildings lack natural ventilation and rely solely on HVAC systems such as centralised air conditioning for ventilation. The pandemic has prompted debates on the efficiency of HVAC ventilation. Let’s see the effect that proper ventilation can have on the spread of COVID-19.
How can ventilation prevent the spread of COVID-19?
Over the course of this pandemic, it has become clear that poorly ventilated indoor spaces pose significant health risks. Obstructed airflow leads to an accumulation of respired air, increasing the risk of spreading the virus. Ventilation alone is not enough to protect you from the risk of the virus indoors; other necessary measures including wearing masks, using hand sanitiser and maintaining social distancing. However, adequate ventilation is a crucial measure to guard against the spread of COVID-19 in indoor spaces. The World Health Organisation (WHO) has even recommended avoiding confined and poorly ventilated spaces and ensuring sufficient ventilation in indoor environments. So, what does this mean for conventional air conditioning where the air is re-circulated instead of replacing it with fresh, clean air?
Ventilation and conventional air conditioners
Conventional air conditioners are designed to re-circulate the air within the spaces that they cool. As they don’t allow free and unregulated airflow from outside, conventional air conditioners heighten the risk of transmitting the COVID-19 virus from one person in a room to another. This brought to light a major flaw of conventional, split-system air conditioning: viruses and particles can be transmitted within closed rooms. Given the current pandemic, this is an issue that needs immediate attention. Since conventional air-conditioning units often have no ventilation component and require the rooms to be sealed, the WHO recommends additional ventilation when using conventional air conditioners. However, we don’t have to forego air conditioning entirely – thanks to personal aircons that offer a viable and more eco-friendly alternative. Let’s see how personal aircons can help.
How can personal aircons help?
Personal aircons are portable – this means you can avoid the costly installation of a bulky wall-mounted unit. This great feature saves you all the trouble from installing the window exhaust, and best of all, you can open your windows and let that cool breeze in! Personal aircons cool the people in the room instead of the room itself by creating a microclimate around them. This allows you to keep your doors and windows open, allowing for natural ventilation. This is a safe and cost-effective way to ensure proper ventilation even while you enjoy the comfort of air conditioning.