help! About air pollution and air pollution index

You can take a look at these two web pages, which also contain tables

/hjkp/about_api.htm

/hjkp/kqzl.htm

Air Pollution Index (API)

The weekly air quality report evaluates the air quality of a city within a week based on the results of routine monitoring of several common pollutants specified in the national "Ambient Air Quality Standards". And released to the public in the form of air pollution index representation.

The Air Pollution Index (AIR POLLUTION INDEX, API for short) is a method to reflect and evaluate air quality. It simplifies the concentrations of several routinely monitored air pollutants into a single conceptual numerical form. It also classifies the air quality status and the degree of air pollution. The results are concise, intuitive, easy to use, and suitable for expressing the city's short-term air quality status and changing trends.

The principle of determining the air pollution index: the quality of air quality depends on the degree of pollution of the most harmful pollutants among various pollutants. The air pollution index determines the classification of the pollution index and the corresponding pollutant concentration limits based on ambient air quality standards and the impact of various pollutants on human health and the ecological environment. The air index classification standards currently used in our country are: (1) The pollutant concentration corresponding to an Air Pollution Index (API) of 50 points is the national air quality daily average first-level standard; (2) The pollutant concentration corresponding to an API of 100 points is the national air quality standard. The daily average quality level two standard; (3) The pollutant concentration corresponding to API 200 points is the national air quality daily average level three standard; (4) The higher API classification corresponds to when various pollutants have different impacts on human health. The concentration limit of API 500 points corresponds to the concentration of various pollutants that cause serious harm to the human body.

According to the characteristics of my country's air pollution and the focus of pollution prevention and control work, the pollutant items currently included in the air pollution index are tentatively determined as: sulfur dioxide, nitrogen oxides and total suspended particulate matter. As environmental protection work deepens and monitoring technology improves, other pollution items will be adjusted and added to reflect the pollution situation more objectively.

Calculation and reporting of air pollution index: The relationship between the pollution index and the concentration of each pollutant is a piecewise linear function (see Table 1 and Figure 1), and the interpolation method is used to calculate the sub-index of each pollutant. In (for specific calculation methods, please refer to "Environmental Monitoring Briefing" Issue 9, 1997), the largest sub-index of each pollutant is taken to represent the pollution index of the region or city. That is:

API=max(I1,I2...Ii,...In)

The pollutant corresponding to this index is the primary pollutant in the region or city. When the pollution index API value is less than 50, the primary pollutant is not reported.

Basic knowledge of daily air quality reports

Like weather forecasts, CCTV will release daily air quality reports to the public in 41 major cities including Beijing, Shanghai, Tianjin, and Chongqing every day. Xiamen City will also in it. In order to let the general public understand the air quality daily report, some basic knowledge of the air quality daily report is introduced in the form of questions and answers.

1. What is air pollution?

Answer: Air pollution refers to the entry of certain substances into the atmosphere due to human production and living activities, which changes the chemical, physical, biological and other characteristics of the atmosphere, affects people's lives and work, and harms the human body. Health, phenomena that affect or endanger the survival of various organisms, directly or indirectly damage equipment, buildings, etc.

2. What factors affect air quality?

Answer: The quality of air quality reflects the degree of air pollution, which is judged based on the concentration of pollutants in the air. Air pollution is a complex phenomenon, and the concentration of air pollutants at a specific time and place is affected by many factors. The size of man-made pollutant emissions from stationary and mobile pollution sources is one of the most important factors affecting air quality, including exhaust from vehicles, ships, and aircraft, production emissions from industrial enterprises, residents' lives and heating, and garbage incineration. Urban development density, topography and meteorology are also important factors affecting air quality.

3. Why should we announce the ambient air quality?

Answer: With the rapid development of social economy and the improvement of industrialization level, human activities have an increasing impact on the environment, especially in cities where a large number of factories, vehicles, and people are concentrated. Due to the above reasons, air quality has gradually begun to deteriorate. Where is it deteriorating? What is the degree of deterioration? What is the development trend? Experts are concerned about it, people are concerned about it, and the government is even more concerned about it. Publicly publishing air quality conditions in the news media is a measure taken by the government to do practical things for the people. It is a basic work for environmental protection work to be in line with international standards. It is not only conducive to the openness and transparency of environmental protection work, but also helps to promote public Increased environmental awareness and participation in environmental protection work. Air quality can be divided into different types according to the reporting time: hourly reports are called daily reports; daily reports are called daily reports; weekly reports are called weekly reports.

4. What are the main pollutants of air pollution?

Answer: Air pollution pollutants include: smoke, total suspended particulate matter, inhalable suspended particulate matter (floating dust), nitrogen dioxide, sulfur dioxide, carbon monoxide, ozone, volatile organic compounds, etc.

5. What pollutants are my country’s current air quality reports mainly based on?

Answer: my country currently stipulates that there are three pollutants that air quality must be based on: sulfur dioxide, nitrogen dioxide, and respirable suspended particulate matter (drift dust). This is based on the national urban pollution situation and the current technical level. Definitely. With the further development of this work and the improvement of technical level, our city will also add other pollution projects based on the characteristics of Xiamen to make it more comprehensively reflect the air quality and pollution status of Xiamen.

6. How are air quality daily reports and cycles reported?

Answer: The air quality daily report mainly relies on the ambient air quality automatic monitoring system to continuously monitor data in real time and automatically transmit it to the central control room. After data processing and calculation, the air pollution index of the day is obtained. Announce to the public. The automatic air quality monitoring system includes high-tech technologies in the fields of automatic analysis technology, automatic control technology, computer technology, and remote communication technology. For example, the oscillating balance method for measuring total suspended particulate matter uses the technology used to measure particulate matter on the space shuttle. equipment. The automatic monitoring system generates a set of monitoring data every 4 minutes, measures it continuously, and then calculates the hourly average and daily average. Generally speaking, the daily average is calculated using the data from 12 noon on the previous day to 12:00 on the next day.

7. What work has our city done in air quality daily reporting?

Answer: Our city started air quality monitoring 20 years ago. In view of the technical level, manpower, and material resource constraints at that time, we could only adopt the method of manual intermittent sampling and laboratory analysis, which has not been possible. Air quality daily report.

Our city introduced air quality monitoring instruments from the United States in 1997, and implemented automatic air quality monitoring in Gulangyu Island and Daxiang Island, and launched a weekly air quality report that year. In 1998, an automatic air quality monitoring system covering the entire island was built, and on May 25, 1998, it became the second city in the country to implement daily air quality reporting after Dalian. At the end of 1999, our city took the lead in launching the Air Quality Times online. According to the work deployment of the Environmental Protection Bureau, an air quality monitoring system covering the whole city will be completed this year, and daily air quality reports for all districts outside the island will be gradually realized. At the same time, we are also preparing to jointly carry out air quality forecast work with the meteorological department.

8. How is air quality assessed?

Answer: my country’s air quality is evaluated using the Air Pollution Index. The air pollution index determines the classification of the pollution index and the corresponding pollutant concentration values ??based on ambient air quality standards and the impact of various pollutants on human health and the ecological environment. The air pollution index (API) currently used in our country is divided into five levels. The API value is less than or equal to 50, indicating that the air quality is excellent, which is equivalent to the national air quality level one standard and is in line with nature reserves, scenic spots and other areas that require special protection. air quality requirements; an API value greater than 50 and less than or equal to 100 indicates good air quality, which is equivalent to meeting the national second-level quality standard; an API value greater than 100 and less than or equal to 200 indicates that the air quality is lightly polluted, equivalent to the national air quality standard Level 3 standard; API value greater than 200 indicates poor air quality, which is called moderate pollution, and is the national air quality level 4 standard; API value greater than 300 indicates extremely poor air quality and is seriously polluted.

9. What effects do different levels of air quality have on the human body?

Air Pollution Index

API air quality status indicates the impact of color on health recommended measures

0-50 You can do normal activities

100-200 Symptoms of people susceptible to mild pollution are slightly aggravated, and irritation symptoms occur in healthy people

Patients with heart disease and respiratory diseases should reduce their physical strength Consumption and outdoor activities

200-300 Moderate pollution significantly aggravates symptoms and reduces exercise tolerance in patients with heart disease and lung disease, and symptoms are common in healthy people

The elderly and heart disease , Lung disease patients should stay indoors and reduce physical activity

>300 Healthy people with heavy pollution have reduced exercise tolerance, have obvious and strong symptoms, and develop certain diseases in advance

Elderly people Patients and patients should stay indoors to avoid physical exertion, and the general population should avoid outdoor activities

10. What is the level of air quality in our city?

Answer: Xiamen is the first country to implement air pollution control measures As one of the cities with daily quality reports, monitoring results show that Xiamen’s ambient air quality remains basically good. The average air pollution index in Xiamen in 1999 was 35, and the air quality excellent rate reached 88.5%.

11. What are the dangers of sulfur dioxide and what is its source?

Answer: Sulfur dioxide is a colorless, moderately irritating gas that mainly affects the respiratory tract. Sulfur dioxide mainly comes from burning sulfur-containing fuels. A large part of sulfur dioxide in the air comes from power generation processes and industrial production. Inhaling sulfur dioxide can impair respiratory system function and aggravate existing respiratory diseases (especially bronchitis and cardiovascular disease). For people who are easily affected, in addition to changes in lung function, there are also some obvious symptoms such as wheezing, shortness of breath, coughing, etc. Sulfur dioxide can also lead to increased mortality, especially when combined with suspended particles. People most vulnerable to the effects of sulfur dioxide include people with asthma, cardiovascular or chronic lung disease (such as bronchitis or emphysema), children and the elderly.

12. What are the dangers of nitrogen dioxide and what is its source?

Answer: Nitrogen dioxide is a brown-red gas with a pungent odor. It mainly comes from vehicle exhaust, fuel combustion in thermal power stations and other industries, and the industrial production process of nitric acid, nitrogen fertilizers, and explosives. It is corrosive and physiologically irritating. People with respiratory problems, such as asthma patients, are more susceptible to nitrogen dioxide. influence. In children, impaired lung development may occur. Studies have shown that long-term inhalation can cause structural changes in the lungs. Nitrogen dioxide is one of the main factors in the formation of photochemical smog and one of the sources of acid rain.

13. What harm do total suspended particles and respirable suspended particles (drift dust) do to the human body, and what are their main sources?

Answer: Total suspended particulate matter can be suspended in the air for a long time. It consists of particles ranging in size from 0.05 to 100 microns. Those smaller than 10 microns are also called inhalable particulate matter (drift dust). Generated from natural and man-made sources, including oceans, soil, vehicle exhaust, industrial activities, construction projects, and gas phase chemical reactions. The impact of total suspended particulate matter in the air on human health depends on the amount of particles that are inhaled and accumulated in the respiratory system. Inhalable particles with a diameter of 10 microns or less can directly reach and deposit in the lungs, causing adverse health effects. The impact of inhalable particulate matter on human health includes causing respiratory discomfort and respiratory symptoms (such as shortness of breath, coughing, wheezing, etc.), aggravating existing respiratory diseases and damaging lung tissue. Therefore, respirable suspended particulate matter (drift dust) has attracted more attention. People most vulnerable to the effects of total suspended particulate matter include people with chronic lung and heart disease, colds or asthma, the elderly and children.

14. How to improve air quality?

Answer: Preventing and controlling air pollution and controlling pollution emissions are fundamental measures to improve air quality. The main ways are: rational industrial layout and good environmental planning; changing the energy structure, promoting clean fuels, and using clean production processes , reduce pollutant emissions; strengthen energy conservation, improve energy utilization, and regional central heating; strengthen environmental supervision and management and the treatment of old pollution sources, implement total volume control and meet emission standards; strictly control motor vehicle exhaust emissions, etc.

Plants have the function of filtering various toxic and harmful atmospheric pollutants and purifying the air, especially forests. Therefore, greening and afforestation is a relatively economical and effective measure to prevent and control air pollution.