In the 1920s, the purification requirements for the production environment were first put forward in the gyroscope manufacturing process of the American aviation industry. A "control assembly area" has been set up in the manufacturing workshop and laboratory to supply a certain amount of filtered air. In the Korean War, the United States found that the main reason for the failure of electronic instruments was the dust, which contributed to the start of air purification technology.

1957年，前苏联颗人造卫星的升空，刺激了美国加速发展宇航事业，制定了阿波罗登月计划，其电子控制仪器和精密机械加工环境均要求净化，因而促进了净化技术的大发展，建造了百级洁净室，誔生了个洁净室标准。

In 1957, the launch of the first Sputnik in the former Soviet Union stimulated the accelerated development of aerospace industry in the United States. The Apollo moon landing program was formulated. The electronic control instruments and precision machining environment required purification, thus promoting the development of purification technology. A hundred level clean room was built, and the first clean room standard was born.

1970年，1K位的集成电路开始大规模生产，使净化技术的发展突飞猛进。20世纪80年代，大规模和超大规模集成电路的生产，使空气净化技术有了进一步的发展，集成电路的更细光刻线宽达到2~3um。在70年代末和80年代初，美国、日本研制出0.1um级空气过滤器，为洁净度的提高创造了条件。

In 1970, the large-scale production of 1K bit integrated circuit started, which made the development of purification technology rapidly. In the 1980s, the production of large-scale and super large-scale integrated circuits made the air purification technology further developed, and the thinnest optical linewidth of integrated circuits reached 2-3um. In the late 1970s and early 1980s, the United States and Japan developed a 0.1um class high efficiency air filter, which created conditions for the improvement of cleanliness.

In the 1990s, the production of VLSI has made new progress. The narrowest optical linewidth has developed from the micron level in the 1980s to the submicron level. By the end of the 20th century, it is required to reach 0.1-0.2um, and the integration degree is 1km. The higher the integration degree of integrated circuit, the smaller the photolithography linewidth required, the smaller the dust particle size required to be controlled, and the smaller the number of dust particles. Nowadays, it is very common to require 0.1um10 class cleanliness. In the future, the required cleanliness will be higher and the application field of clean room will be wider.

在2001年中国科协学术年会上，杨振宁教授指出，在今后三四十年，三个领域将成为科技发展的“火车头”：① 芯片的广泛应用。 ②医学与药物的高速发展。③ 生物工程。芯片需在工业洁净室中生产，药品需在生物洁净室中生产，医学研究、生物工程都离不开生物洁净室。对于有生物学危险的操作，需要在生物安全洁净室中进行。工业洁净室、生物洁净室及生物安全洁净室，都是应用空气净化技术创造的特殊的微环境。

In 2001, Professor Yang Zhenning pointed out that in the next 30 to 40 years, three fields will become the "locomotive" of scientific and Technological Development: ① the wide application of chips. ② The rapid development of medicine and medicine. ③ Bioengineering. Chips need to be produced in the industrial clean room, drugs need to be produced in the biological clean room, medical research and bioengineering are inseparable from the biological clean room. For operations with biological hazards, they need to be carried out in the biosafety clean room. Industrial clean room, biological clean room and biosafety clean room are all special micro environments created by air purification technology.

电子产业的飞速发展，将推动中国净化技术向高水平发展，而医学与药物的快速发展，必将使空气净化技术的应用更加广泛。中国在制药行业实施GMP（Good Manufacturing Prac-tice）认证制度以来，生物洁净室的兴建像雨后春笋，给净化技术产业带来的繁荣。近年来，三级甲等医院纷纷建造洁净手术部，使术后感染率降低10倍以上，从而可以少用或不用抗生素，减轻了抗生素对患者造成的伤害。这也将进一步拓宽净化技术的应用领域。

The rapid development of electronic industry will promote the development of China's purification technology to a high level, and the rapid development of medicine and medicine will make the application of air purification technology more extensive. Since the implementation of GMP (good manufacturing prac tice) certification system in the pharmaceutical industry in China, the construction of biological cleanrooms has mushroomed, bringing unprecedented prosperity to the purification technology industry. In recent years, the third class A hospitals have built clean operating departments, which can reduce the postoperative infection rate by more than 10 times, so that antibiotics can be used less or not, reducing the harm of antibiotics to patients. This will further expand the application of purification technology.

2003年SARS病素肆虐，使人们对空气传播病毒的危险性有了深刻的认识。更值得反思的就是医院建筑，不仅要注重建筑外形与使用功能，更应该关注建筑内的空气品质。据了解，人吃进1亿个兔热杆菌才感谢染，若吸入10~50个就发热。这给只重视接触感染而轻视气溶胶传播的呼吸道感染的医护人员敲响了警钟。因为气溶胶传播更具有爆发性、低感染剂量和大范围的特点，危险性极大。因此，现代医院建筑应有空气净化设备，才能保证医患人员的安全。应装配空气净化系统的医院建筑有：洁净手术部、生物治疗实验室、传染病人隔离室、营养液配制、制剂、无菌物品供应等。这将给净化技术的应用带来新的机遇。

In 2003, SARS was rampant, which made people have a deep understanding of the risk of air borne virus. The most worthy reflection is the hospital building, which should not only pay attention to the shape and function of the building, but also the air quality in the building. It is understood that people eat 100 million rabbit thermobacilli to thank for infection, if inhaled 10-50, they will get fever. This is a wake-up call for medical staff who only pay attention to exposure to infection and despise aerosol borne respiratory tract infection. Because aerosol transmission is more explosive, low infection dose and large-scale, it is very dangerous. Therefore, modern hospital buildings should have air purification equipment to ensure the safety of doctors and patients. The hospital buildings that should be equipped with air purification system include: clean operation Department, biological treatment laboratory, isolation room for infectious patients, nutrient solution preparation center, preparation center, sterile supplies center, etc. This will bring new opportunities to the application of purification technology.

在21世纪，生物工程对人类的直接影响将超过芯片，而其发展离不开空气净化技术。如生物工程中有相当一部分操作存在潜在危险性，特别是存在可能具有未知毒性的微生物新种传播生物学危险。这就需要提供具有生物安全的建筑微环境，可利用空气净化技术、生物安全知识来建造生物安全洁净室来控制这种具有生物学危险的污染的传播。

In the 21st century, the direct impact of bioengineering on human beings will exceed that of chips, and its development cannot be separated from air purification technology. For example, in bioengineering, there are potential risks in a considerable part of operations, especially in the transmission of new microbial species with unknown toxicity. Therefore, it is necessary to provide a building micro environment with biosafety. Air purification technology and biosafety knowledge can be used to build biosafety clean rooms to control the spread of this biologically dangerous pollution.