Over the past few months, COVID-19 has become the biggest concern for people around the world. To prevent the spread of coronavirus, we need to keep social distancing and ultimately change our lifestyle completely. On the other hand, PM 2.5, one of our major concerns since the beginning of the year, has become something that people were talking about less and less. Yet the problem is still there. Road transport contributes to 50% of PM 2.5 in the air, according to the Pollution Control Department. In Bangkok alone, we have over 10 million registered vehicles. That means no matter how long we have to deal with COVID-19, PM 2.5 will continue to be one of the biggest concerns. It will continue to be a major environmental problem and Thais will have to come up with ways to solve it.