Winter Is Here — Why Does PM2.5 Rise in the Cold Season? Causes and Practical Protection
Winter is here — why does PM2.5 rise in the cold season? Let's look at the causes and how to protect ourselves.
Winter in Thailand mostly runs from early November to late February, spanning roughly 4 months — a little more or less from year to year. Normally, winter in Thailand isn't bitterly cold but rather pleasantly cool, with general temperatures around 15–30 degrees Celsius, except in the North and Northeast, particularly on mountain peaks, where it can get cold enough to occasionally produce frost or rime. In southern Thailand, it mostly isn't cold but turns into the rainy season instead (on top of the rainy season it already has).
But did you know? In winter, besides the air turning much cooler, the level of airborne dust — PM2.5 — also rises above that of other seasons. As for the reason why, along with how to care for and protect your own health from dust in winter, today Sanyawit has gathered some useful information to share with you in this article. If you're ready, let's explore it together!
Did you know? Why you need to be especially wary of PM2.5 in winter
Normally, the air just above the ground is warmer than the air higher up in the sky, and air moves from areas of higher temperature to lower temperature (ground → sky). Under normal conditions, the warmer air above the ground rises into the higher layers of the atmosphere, carrying with it the dust, smoke and other things mixed into the air.
During winter, or late winter, Thailand comes under a high-pressure system spreading down from the north, lowering temperatures across the country. This causes the ground to radiate heat rapidly, so the air above the ground begins to cool as well. These factors change the movement of the air, in what is called a temperature inversion — warm air becomes wedged in the middle, forming a thick barrier like a ceiling, so the air doesn't circulate normally: no wind, no air exchange — what is known as "closed air." So on closed-air days, which occur during winter, PM2.5 levels spike, because the dust is held in by this ceiling-like barrier and prevented from rising into the atmosphere, accumulating in the sky — sometimes even visible to the naked eye. When the air opens up again, or the high-pressure system passes, the air can move normally and the fine PM2.5 particles thin out on their own.
But waiting until the air opens up seems a bit too long to wait, because Thailand's winter lasts as long as 3–4 months, during which everything around us is full of PM2.5. Leaving it for a long time without doing anything could affect our health and quality of life. So what you should do is find suitable ways to deal with dust in winter, before your health declines to a point that is hard to reverse.
Sanyawit has the following recommendations for how to conduct yourself in winter:
4 recommendations from Sanyawit to help you cope with PM 2.5 during winter
- Check the dust level before leaving home
Sanyawit recommends everyone keep checking PM2.5 news from various media, or check the level of airborne dust before leaving home as a routine, by checking the Air Quality Index (AQI), which can be checked via a website or a mobile app. But for anyone who wants to check local air quality in real time, there are now many portable airborne-dust meters on the market, ranging from affordable to higher prices, which you can buy to check dust readings in real time, for better protection of your own health from dust.
- Wear a face mask or an N95 mask if you must stay outdoors for a long time
On closed-air days when PM2.5 spikes, you should refrain from leaving home and avoid outdoor activities. But if it is necessary to go out, you should wear a face mask or an N95 mask at all times to avoid inhaling PM2.5 into the body.
Or in the case of any company or office whose work involves dust — such as work on the roads or at construction sites — these groups should consider choosing an N95 mask, which protects against PM 2.5 better than an ordinary face mask, because these workers are exposed to dust both from the work itself and from PM 2.5.
- Check the performance of your air purifier and its filter
For anyone who has already bought an air purifier for the home, don't forget to check whether the quality of the purifier's filter is still working at full capacity. With some newer-model air purifiers, you can check what percentage is left before the filter needs replacing; or if your air purifier can't give that alert, try inspecting the filter inside the unit to see how much dust has built up — if it's a lot, it may be time to replace it. Or, best of all, if you can't remember how long it has been in use, replace the filter immediately, so the air purifier works at even fuller efficiency.
- Replace your air purifier with a new one suited to protecting against PM2.5
In some cases, replacing the filter may still not be enough, because the air filters in many models on the market cannot capture fine particles like PM2.5 — they can only capture larger dust to keep the air in that area from getting too dirty. But if you measure the dust readings carefully, you'll find quite a lot of dust still remaining.
So replacing your air purifier with a new one that genuinely meets your needs is very important. Sanyawit recommends the HCU infection-control air purifier — an innovation engineered for genuinely clean air. Because the HCU is fitted with a HEPA Filter rated as high as 99.999% at 0.3 microns, it can screen fine airborne contaminants many times more effectively than ordinary air purifiers on the market — filtering out dust, pollution, pathogens and bacteria, and the tiny dirt particles that spike in winter — thoroughly and worry-free.
And because the HCU air purifier delivers high airflow yet runs at a quiet 50 decibels, it does not disturb work or daily living, and can be installed in a bedroom or a patient's room without disrupting rest. Every HCU unit has passed third-party hospital clean-room standard testing, so you can be confident in its performance — delivering thoroughly clean, contaminant-free air without a worry: one unit that handles every airborne-pollution problem.
Beyond its medical-grade performance, the HCU infection-control air purifier can also filter airborne dirt quickly. Simply install it correctly and switch it on properly, and the HCU will gradually screen out the dust, smoke, pollution and pathogens around you, swiftly transforming pollution-filled air into clean air. You can measure the results with an airborne-dust meter right away, a short while after switching the HCU air purifier on.
Because we believe "the best investment" is investing in health — not just your own health, but the health of everyone living under the same roof too. With good air around us, keeping ourselves healthy is no longer a difficult task. Homes with young children, the elderly or people with various illnesses should especially have an effective air purifier in the home. Don't let the home that should be your safe zone become a breeding ground for airborne pathogens — because you can improve the air quality in your home at any time, simply by using our HCU infection-control air filter.
Sanyawit — a leading provider of clean-air system products and solutions, with air-pollution control coverage worldwide, delivered by a team of professionals experienced directly with leading hospitals — to meet our customers' needs with quality products that fit every use and clear away their problems.
If you are interested in owning an HCU infection-control air purifier, feel free to contact us any time.