Maybe many people think that the morning air is the best, but this is not necessarily accurate.

In the early morning, the impurities floating in the air the day before were deposited in the air for a night, accumulating in the air close to the ground, causing the air to be not too fresh, and by the morning peak of work, the number of vehicles driving increased, the air quality of the car exhaust It is even worse.

In fact, the air quality is good at around 10 am and 3 to 4 pm, because people are less active at this time, and in the case of solar heating, the flow of air does not cause impurities to accumulate in the atmosphere near the ground. In the air, the air is relatively fresh, so usually about 10 am and 3 to 4 pm, the air will be fresher.