If you have been following me on Twitter
, you would know that I’ve been highlighting the dangers of being in unventilated spaces during a global pandemic. This is because Covid-19 is airborne
and aerosols with viruses can linger in the air for hours. There’s no cheap way of detecting if Covid-19 is present in a room, but you can use a CO2 meter as a proxy to work out the risks. For example, anything over 800 ppm means that you are breathing in the air that has already been in someone else’s lungs. You don’t need me to tell you of the risks you are taking if someone in the room has Covid-19 or any other airborne virus. And it doesn’t matter if they have already left as the aerosols will linger for several hours afterwards.
Of all of the places that I have tested for CO2 on my travels, the taxis in Bangkok are potentially the most dangerous. More so than cinemas, supermarkets and even long airplane flights. In the photo above, you can see that as soon as I got in the taxi, the reading went from around 500 ppm to 2778 ppm. I’ve been in taxis before where it went as high as 3200 ppm. You definitely need a tight fitting N95 masks for taxis. A regular surgical mask offers no protection. So, what can you do to lower your risk? The first thing is to ask the driver to turn off the “recirculation” button. This then brings in air from outside. As you can see in the photo, within ten minutes it had dropped to an acceptable 677 ppm. You could also open a window. But from my experiments, you need to open the front left and back right window which will change the air quicker than just one window alone.