The height of the floor and the amount of flying dust cannot be generalized

On Saturday, the author met a young couple who were choosing a new house at the sales office of Chengnanrun and Nan'an Flower City. "We plan to get married next year, so we must choose a house that we like, and it seems that the high-rise is the most suitable for our taste......In their opinion, the high-rise is fashionable and beautiful, which fully satisfies their mentality of pursuing trends.

When the author asked about the choice of floors, the young couple said that the high-rise is known as a "high-end residence". So we also want to choose a higher floor, because we are afraid that the house will be too dusty and it will be troublesome to clean.

In fact, many home buyers, like this young couple, also like high-rise homes, but worry that their new home in the future will "attract dust" because of the high floors. They think that the dust runs upwards, and the 9 and 11 floors are the floors with the most dust distribution, so will the choice of high floors be in close contact with the "flying dust" in the air?

With the above questions in mind, the author interviewed relevant professionals. Experts believe that the "flying dust" in most citizens' understanding is actually a layer of raised ash. Due to the influence of the airflow in the air and the building microenvironment, the dust density of the building in a certain height range is relatively large, but it is not necessarily concentrated in the 9 11 floors of the high-rise.

It varies from city to city, from region to region and even from neighborhood to neighborhood, depending on the density of dust, the height of surrounding buildings and the characteristics of the airflow. In other words, the "ash layer" of different buildings is not the same and cannot be generalized. Therefore, it is not necessarily that the lower floors of the house are less dusty.

There is no direct correlation between the elevation of the floors and the dust, and almost all residents living on the 9th and 11th floors of high-rise buildings do not have a particularly "badly fallen ground" feeling.

So how can we better avoid the ash layer? Experts suggest that when choosing a building, we should pay attention to the surrounding geographical environment and greening facilities, and try to choose a building around the river and by water, because water has a good purification effect on the air, and generally the buildings that rely on water have less dust, and the air quality is relatively high-quality. In addition, when choosing a high floor, try to choose more than 5 floors, after all, the advantage of a high-rise is still in the open view.

The best floor options are between 6 8 and 13 16 floors, depending on the buyer's personal preference. Finally, professionals suggest that residents who have purchased high-rise buildings should reduce the number of window openings, high-rise buildings are greatly affected by wind, so it is best to open the windows for 1 2 hours in the morning or morning every day, the air clarity is the highest in the morning, choose to open the windows in the morning, so that the air has enough convection space, which can effectively prevent the invasion of dust, and create a natural and fresh environment for the house.

The dust is concentrated on the three floors of 9-11, which is about 30 meters above the ground at a fixed height. Above and below these three floors, there is no need to worry about flying dust.

Because of the convection caused by solar radiation, the pre-existing wind and other factors, the distribution of dust is not so easy to concentrate on a certain layer or several layers, in fact, most people observe that the higher the floor, the more likely it is to get dirty, which is mainly because the high floors are prone to dust.

In fact, the higher the floor above the ground, the cleaner the air. Gaseous pollutants such as sulphur dioxide, nitrogen oxides, carbon monoxide, and particulate pollutants such as PM10, as well known as PM10, decrease with floor height. If the residence is close to shopping malls, downtown areas, roadside barbecues, restaurants, etc., relatively speaking, the air quality is relatively good if you live on the upper floors.

The higher the floor, the more dusty it is. Air pollutants mainly include suspended particulate matter and other gaseous pollutants. Suspended particulate matter mainly includes coal ash, sand, ash, etc., under the action of air flow, these suspended particles will be suspended in the air, but because of gravity, they will eventually fall back to the ground, and will not be rashly displaced to an altitude of 30 meters.

Therefore, the density of suspended particulate matter decreases with increasing height. In other words, the higher the floor, the less dust.

According to the test results of the laboratory staff of the Environmental Protection Agency, it is not the dust concentration on the 9-11 floors that is the highest, but the real result is that the concentration and PM10 concentration basically decrease with the increase of height, and the highest value is not measured on the 9-11 floors, so the dust concentration on the 9-11 floors is not the highest.

The experimenter used a hand-held air measuring instrument to take five air samples at each layer, and then measured the concentration of PM10 separately. The measured data on the first floor is 18, and PM10 is 40; 15 to the 9th floor, 30 PM10; When I got to the top 25th floor, it was 13, which is 5 less than 18 on the first floor. Through such a comparison, the dust concentration on the 25th floor is the lowest, and the 9th-11th floor is also in the middle of the measured values.

The experimenters conducted another test in two other high-rise buildings, and the concentration measurements obtained on each floor did not differ much, so the statement that "floors 9-11 are ash floors" is not valid.

The test results also show that the higher the floor, the better the air, but factors such as the surrounding environment can also have a great impact on the values. Because the particles are very small, the flow of air through the air will mix very evenly, and there will not be much difference between living on the 10th or 20th floors as the height increases. At the same time, it is also directly related to meteorological conditions and surface conditions, such as wind, rain, air pressure and temperature will also directly affect the quality of air quality.

The floating dust layer is generally 30-40 meters from the ground, and the building height of the building is 3 meters, which should be between 9-12 floors.

The floating dust layer refers to the level where the floating dust in the air is located, that is, the floating dust layer of the air, which is the dividing line for the less floating and subsidence, that is, the air above the floating and sinking layer will be better.

I feel that the height of the middle floor should be the cleanest, the low floor is the easiest to attract dust, due to the effect of the wind, the upper floor is also easy to attract dust, and the middle floor is the best!

No, there is no scientific basis for this. It still depends on the surrounding environment where you live.

To be specific, what does it mean is not necessarily, it is related to the wind direction, and I personally understand that the lower it is, the more dust, after all, the low-altitude pollution is serious, and it is closer to the range of human activities......

This is not necessarily, first look at the air environment of the place where your building is built.

There is no such statement.

The air quality is better with higher floors.

It seems that yes.

The dust is going up.