AIR CONDITIONER IN COVID-19 CRISIS

Should compromise Comfort for COVID-19

With the outbreak of COVID-19 there are speculations going regarding the usage of air conditioners through social media. I have gone through the latest guidelines provided by the ISHRAE and excited to share via my blog.

In the present article I would like to limit with Room Conditioners as most of the commercial activities are not operational.

Effect of Environmental Conditions on COVID-19:

• Relative Humidity:It is found to affect the infectivity (the ease with which infection can take place) of virus through the respiratory route. When we breathe dry air the mucous membrane in the lungs become dry. The fluid over lining the cells becomes more viscous, and the little hairs called cilia, which protect our lungs from deep settling of viable & non-viable particles, cannot work and particles settle more deeply in the lungs. If we consider oxygen & CO2 transport and the blood, it is only one cell membrane that separates the airspace from the blood. So, if something goes from our lungs into the blood, we get infected. 

• Moisture in the air is the first arm of our immune system and we now know that our body cannot fight off foreign particles or invaders as adequately as when we're in a dry environment.
• All things considered, the relative humidity level of 40%~70% is considered to be the most suitable environment for humans & decreases problems from pathogens

•  Temperature: It tends to be a factor that directly affects the comfort of building or hospital occupants.
• Normal comfort conditions:24 to 30 degree centigrade(depends upon the individual and physical activity).
• Studies conducted at various RH levels have shown that using viral culture methods low temperatures (7–8 °C) were optimal for airborne influenza survival, with virus survival decreasing progressively at moderate Temperatures (20.5–24 °C) and further decreases at higher (greater than 30 °C) temperatures.
• As per some recent studies, SARS-CoV-2 has been found highly stable on surfaces for 14 days at 4 °C; one day at 37 °C and 30 minutes at 56 °C were needed to inactivate the virus.

• Room Air conditioners:
• Room air conditioners re-circulate air within a single occupied zone. 
• This is the main limitation of the room air conditioners.
• To overcome this, the room need to be ventilated properly by slightly opening the  window. This will allow to introduce fresh air in the room.

Slight opening of a window

• People close the openings in the room (especially provided at the top) to make air not to escape. This will not allow air to move outside and which in turn  increases carbon dioxide levels. The increased levels of carbon dioxide is not a healthy sign.
•  The closing of openings will also build pressure in the room and not allowing fresh air to enter. 
• Not ventilating room will create dizziness and one may feel lightheaded.

• Evaporative Coolers:

• Evaporative coolers, often known as desert coolers provide effective cooling in Hot and Dry Climates. A Fan draws hot and dry outdoor air over water-saturated pads, causing the water to evaporate and cool the Air. Air leaving the Evaporative Cooler, is up to 15°C cooler than outdoor air, is directed inward.
• Evaporative cooler tanks must be kept clean and disinfected and the water drained and refilled frequently.
• Evaporative coolers must draw air from outside to ensure good ventilation.