An introduction to particulate matter sensors

User:JXCTUpload time:Aug 18 2022

Air is a precious natural resource. But air pollution is increasing because of industrial production and human activities. Currently, air pollutants include carbon monoxide (CO), nitrogen oxides (NOx), hydrocarbons, sulfur oxides, and particulate matter (PM). Among them, the level of fine particulate matter (PM2.5) has become one of the important indicators to detect air quality. High levels of PM2.5, the tiny particles in the air, can affect people’s health. Therefore, dust monitoring and reducing PM2.5 levels are very important for the environment and human health.We can use the particle sensor developed by JXCT for online monitoring.

What is PM2.5?

PM2.5 is particulate matter in the atmosphere with a diameter of 2.5 microns or less, also known as particulate matter that can enter the lungs. Its diameter is less than 1/20 the thickness of a human hair. PM stands for particulate matter. Although PM2.5 is only a small part of the composition of the atmosphere, it has an important impact on air quality and visibility. Compared with the coarser atmospheric particulate matter PM10, PM2.5 particle size is smaller, contains a large number of toxic and harmful substances, residence time is long, transport distance is far. PM2.5 and PM10 have different effects on human health. PM10 particles are large and rarely enter the lungs, but PM2.5 is easily inhaled into the lungs, causing a variety of respiratory diseases.

Particulate matter larger than PM2.5 can be intercepted by our nose hair and respiratory secretions, but PM2.5 pollutants are small, highly active and easily carry harmful substances (such as heavy metals and microorganisms). Most of them enter our lungs through breathing, causing conditions such as asthma, bronchitis and cardiovascular disease. It can be suspended in the air for a long time, so the haze caused by fine particulate matter is even more harmful to human health than sandstorms.

The composition of PM 2.5 is very complex, mainly composed of organic compounds, sulfates, nitrates, ammonium salts, carbon and various metal compounds. It consists of a variety of chemicals and particles, which can be part solid particles and part liquid. Particulate contaminants that consist wholly or partly of liquid droplets are called aerosols.

What causes PM2.5 pollution?

Although natural processes produce PM 2.5, the main source is anthropogenic emissions. PM 2.5 from human activities is divided into direct and indirect emissions. Direct emissions are mainly from combustion processes, such as fossil fuel combustion, biomass combustion, vehicle exhaust and waste incineration. Indirect emissions are gaseous pollutants (such as sulfur dioxide, nitrogen oxides, ammonia, and volatile organic compounds) from industrial activities that react with water vapor and sunlight in the air to convert to PM 2.5. Because of many uncertainties, such as region, weather, climate and human activities, it is impossible to tell exactly which chemicals are contained in PM 2.5 particles.
Indoor particulate pollution mainly comes from outdoors in windy sand or bad weather. If the outdoor air is clean, the factors affecting indoor PM 2.5 level mainly include smoking, kitchen cooking, interior decoration, secondary household dust, animal hair and so on.

What are the harmful effects of PM?

Multiple health studies have found that higher levels of PM2 5 pollutants in the air increase negative effects, including increased incidence of respiratory disease, worsening symptoms of respiratory disease, leading to heart attacks and death.

Excessive inhalation of PM2.5 can increase the incidence of respiratory, cardiovascular, reproductive and immune systems, as well as the incidence of mental illness. People living in cities with high levels of air pollution have a 10-15% higher risk of developing lung cancer than cities with relatively clean air. Smoke increases the risk of cancer more than smoking and increases the incidence of chronic cough, asthma and bronchitis.

A US investigation into the relationship between PM2.5 and blood pressure found that for every 10ug/M3 increase in PM 2.5 concentration, subjects’ mean systolic blood pressure increased by 8.6mmHg. Another study found that concentrations of PM 2.5 increased the risk of death in heart disease patients. If the concentration of PM 2.5 exceeds 10ug/M3, the death rate of heart disease patients will increase by 20%.

Particulate matter can also affect the weather. It is widely believed that PM2 5 is simply air pollution. In fact, the effect of PM2 5 on the weather may be even more severe. PM2 5 can affect rainfall process and indirectly affect meteorological change. In addition to seawater salinity, particulate matter is also an important source of rainwater condensation nuclei in the atmosphere. If the amount of PM2 5 is too large, it will absorb water from the sky, so that the cloud droplets in the air will not grow, and white clouds will become fewer than before. In addition, PM2.5 increases the number of condensation nuclei and increases the number of raindrops in the sky, which can cause heavy rain in extreme cases.

How to measure PM2.5?

To monitor PM2 5 levels indoors or outdoors, there are a variety of air quality sensors available on the market for customers to choose from. For different places, we can choose the appropriate PM2 5 sensor.

Particulate matter sensor-PM2.5/10 monitoring-dust sensor

The laser particulate matter sensor is a sensor that uses the scattering principle to detect dust particles in the air. It has small size, high detection accuracy, good repeatability, good consistency, real-time response and continuous collection, strong anti-interference ability, and must be tested and calibrated at the factory. Etc

Particulate matter sensor (dust sensors) can be used for air monitoring in industrial plants/traffic tunnels/automobile exhaust/smog monitoring and other industrial and agricultural environments (pollution emission monitoring, atmospheric environment).

Particulate matter sensor module – dust sensor – pm2.5/10

The laser particulate matter (dust) sensor module adopts the principle of laser scattering, which can monitor the concentration of PM1.0/2.5/10. The particulate matter sensor module adopts a built-in shielding cover, and the internal anti-interference is more precise and the measurement is accurate.dust sensor module is used in air purifier, air quality detector, fresh air ventilation system, air conditioning with air purification function, automobile and supporting agricultural greenhouse of consumer electronics, outdoor breeding place, environmental monitoring, kitchen and bathroom ventilation control system, smart home equipment and other scenes.

Air Quality Monitoring System-SO2,NO2,CO,O3 ,pm2.5,pm10

Air quality monitoring station, grid air environment monitoring system, micro air monitoring station are used to provide products for real-time and accurate monitoring of outdoor air pollutants. The air quality monitoring station adopts an integrated sensor, which is light and small, beautiful in appearance, and easy to install. It can be calibrated according to the site, and customers can choose corresponding products according to specific needs or environments. The air quality monitoring system is used to provide products for real-time and accurate monitoring of outdoor air pollutants. The air quality monitoring system integrates “Four Gas and Two Dust” (SO2, NO2, CO, O3, PM2.5, PM10) sensors combined with wireless communication technology to achieve real-time data monitoring, and collect environmental big data on the “cloud platform” to provide a network The grid platform provides a data foundation.