The new device of China Academy of Sciences boosts the domestic particle count measurement level

It is reported that the clean air particle count measurement and calibration device researched and established by the China Institute of Metrology (hereinafter referred to as China Metrology Institute) has improved the measurement level of particle counts in China and solved the problem of the long-term dependence on foreign imported instruments in this field. China's particle counter production capacity and international competitiveness.

Cheng Huiling, the project leader and the Institute of Chemistry at China Institute of Metrology, said that particulate pollution in the air is the main source of pollution in many industries. Accurate assessment of air cleanliness has become a requirement in many industries for production and product testing. For example, in the electronics industry and the chip manufacturing industry, the deposition of fine particles in gases can cause even greater damage to electrical bad features. In particular, chip line widths have reached micron and submicron levels in recent years, which raises higher requirements for air cleanliness in the factory building. In addition, in modern medicine and pharmaceuticals and bioengineering, the “GMP GMP for Pharmaceutical Manufacturing Practices” formulated and implemented by all countries in the world, including China, places emphasis on the requirements for the cleanliness of particulates in the air during drug production. In particular, with the implementation of the National Outline for Medium- and Long-Term Scientific and Technological Development Planning, core electronic devices, high-end general-purpose chips, and major new drug innovations, which are 16 major development projects, will be rapidly developed, which will enable the measurement of particle counts and Monitoring becomes more urgent.

The dust particle counter is an instrument for measuring the number and particle size distribution of dust particles per unit volume in a clean environment. It can be widely used in drug testing institutes, blood centers, epidemic prevention stations, disease control centers, quality supervision agencies and other authoritative institutions, and biological, pharmaceutical, semiconductor, optical or precision machining and other manufacturing enterprises.

“It is estimated that there are more than 10 dust particle counter manufacturers in China, and the number of Taiwan-used desktops should be no less than 30,000. These manufacturers and users have a very strong demand for calibration testing.” Cheng Huiling said, to ensure To measure the accuracy of dust particles in the air, you first need to ensure that the dust particle counter itself is accurate and traceable. The China Institute of Metrology completed the study and established a standard particle counter calibration device to achieve calibration and calibration of particle counter indication error, relative error of particle size setting, and particle size measurement resolution calibration items for standard particle counters. The uncertainty is 6.0% (k=2), which is better than the technical level of the same foreign calibration and calibration device. At the same time, they also established a working-level particle counter calibration device to achieve effective calibration of particle error indications at the working level (laboratory, portable) particle counter.

"In the study, we traced the particle counter value of the standard particle counter to the country through the use of the international advanced 'laser particle counter - condensation particle counter - aerosol electrometer (or scanning electron microscope)' step-by-step traceability method. The current standard and the traditional microscopic counting method ensure the traceability and accuracy of particle counting." Cheng Huiling thinks this is a major innovation in the project.

Cheng Huiling introduced that through the implementation of the project, a measurement calibration device and a traceability method for dust particle counters in China have been established. The calibration device established fills the gap of China's dust particle counter physical measurement standards, providing a solid basis and guarantee for the traceability and transmission of dust particle counters in China, and effectively promotes China's "Dust Particle Counter" national calibration specification and "Dust Effective implementation of particle counter performance test method.