How  design the lighting in the clean room/clean workshop

　　With the rapid development of science and technology, new technologies, new processes, and new products continue  emerge, and there are more and more construction projects that require clean production environments. At present, clean technology has been widely used in microelectronics, biopharmaceuticals, surgical medicine, Important departments such as precision instrument manufacturing and medical equipment. Let's talk about the lighting design of common large-space enclosed dust-free workshops below:

　　1. Determining the illuminance of the clean room and selecting the light source

　　Dust-free workshops are generally closed workshops with large grids, large spans, large spaces, and no daylight windows. The "Code for Design of Dust-Free Workshops" GB50073-2001 clearly stipulates the illuminance value of daylight windows and dust-free workshops (see the specification Table 9.2.3), and stipulates that the general lighting in the mixed lighting of the clean area without lighting windows is not less than 200 1x, which is one level higher than the 150 1x in GBJ73-84. The International Commission on Illumination (CIE) "Guide  Indoor Lighting" stipulates that the minimum illuminance of a windowless facry building cannot be less than 500 1x. According  my country's current power level, the illuminance standard of artificial lighting in my country is generally lower than that in Europe, the United States and other countries. In fact, the illuminance of some Sino-foreign joint ventures and wholly foreign-owned dust-free workshops is much higher than 2001x, reaching 300~500 1x. For operars working in a closed dust-free workshop, providing them with a bright and comfortable visual environment can greatly improve production efficiency and the yield of fine products. Therefore, it is beneficial  appropriately improve the artificial lighting illuminance level of the dust-free workshop, improve the visual hygiene of the staff, and promote the development of the national economy. The country is currently formulating the "Industrial and Civil Building Lighting Design Standards", and the illuminance standards in the new specifications will be greatly improved. However, considering the light and shade adaptation of the production workshop, the illuminance of the aisle and lounge of the dust-free workshop should not be o different from the illuminance level of the work place. Generally, a difference of 1  2 levels is more appropriate, but the minimum should not be less than 100 1x. The standard for window-free dust-free workshops is the same as that of ordinary production plants in accordance with the current national standard "Lighting Design Standards for Industrial Enterprises" GB50034-92.

　　The illuminance of different clean industrial plants varies greatly according  the process requirements. For example, the illuminance of the mixed lighting of the electron gun assembly workshop of the picture tube facry must reach 1000~3000 1x. In addition  the general lighting, local lighting is also required. Local lighting accounts for The proportion of the mixed lighting illuminance should not be o large, and the general lighting illuminance is 5~15% of the mixed lighting illuminance. Due  the shortage of electricity in my country, the proportion of local lighting in mixed lighting has been expanded. If the space illuminance is low, it is easy  produce glare and make people feel tired, but the brightness of the light source should not be o high, and linear light sources such as fluorescent lamps or incandescent lamps with frosted glass are often used.

　　Secondly, in dust-free workshops that have special requirements for light sources, such as the phosphor coating room in the picture tube facry and the lithography room in the semiconducr facry, in order  prevent the phosensitive material from being exposed  light, yellow or red light sources must be used. For special requirements, use yellow fluorescent tubes or low-pressure sodium lamps. There are also two types of yellow fluorescent tubes. One is coated with yellow phosphor on the inner wall of the tube; the other is white fluorescent tubes with yellow plastic sleeves. Their luminous flux is higher than that of ordinary fluorescent lamps. low.

　　2. Selection and layout of general lighting fixtures in dust-free workshops

　　In order  do a good job in the lighting design of a clean room with a high level of cleanliness, first introduce the cleanliness level of the clean room and the flow pattern of clean air. In the new "Code for Design of Clean Workshops" GB50073-2001, many amendments have been made  the air cleanliness levels. GBJ73-84 stipulates that the air cleanliness is divided in 4 levels, namely 100, 1000, 10000 With the rapid development of microelectronics and integrated circuit industry, the requirements for air cleanliness in dust-free workshops are getting higher and higher. It is required  control the particle size of dust particles below 0.1 ?m. In order  be in line with international standards, new regulations Equivalent  adopting the relevant regulations in the international standard ISO14644-1, the air cleanliness level has been increased from 4 levels  9 levels, namely level 1 and level 2. . . . . . Level 9.

　　In the specification, the selection of the flow pattern of clean air is also clearly stipulated. “For air cleanliness grades 1  4, vertical unidirectional flow should be used; when air cleanliness grades are required  be grade 5, vertical unidirectional flow should be used. Unidirectional flow or horizontal unidirectional flow; for levels 6-9, non-unidirectional flow should be adopted." The so-called air flow pattern is the reasonable design of the flow pattern and distribution of the air in the clean room. Its characteristics: consideration should be given  avoiding or reducing turbulence, which is conducive  the rapid and effective removal of pollutants, and the spread of dust and bacteria from indoor pollution sources should be limited and reduced as much as possible, and the air cleanliness level required by the indoor production environment should be maintained.

　　Due  the particularity of the clean room, the general lighting fixture should be selected with a smooth exterior surface, less uneven surface, no dust accumulation, easy cleaning, and use of materials that are not suitable for generating static electricity. In addition  meeting the illuminance requirements, the selection and layout of lamps should also be considered based on the indoor air flow pattern. When the ceiling is a vertical unidirectional flow air outlet, such as the phoetching workshop of a very large scale integrated circuit facry. . . . . . , The area of ??the air outlet of the high-efficiency filter can sometimes reach about 80% of the ceiling area, which brings difficulties  the layout of the lamps. At this time, teardrop fluorescent lamps should be used. This kind of lamps has less influence on the airflow and can be installed in The lower side of the special aluminum profile frame for the high efficiency filter (see Figure 1 and Figure 2) not only does not hinder the air supply, but also effectively utilizes the only ceiling space. Depending on the ceiling module, different lengths of lamps can be selected.

　　Recently, Matsushita Electric Works (China) Co., Ltd. has launched a new type of clean light FPC41808, which is similar  the teardrop fluorescent lamp. It adopts a streamlined design  avoid turbulent eddy currents, which can prevent dust accumulation and obtain smooth and stable airflow. Can also be used.

　　For non-unidirectional flow clean rooms, triangular ceiling fluorescent lamps or cassette ceiling fluorescent lamps should be used. The arrangement of lamps is preferably continuous light belt type or intermittent light belt type, and unified arrangement with fire alarm detecrs, air-conditioning vents, etc. . For example: the electron gun assembly workshop of a picture tube facry, with an area of ??2160┫ (60×36), uses double-tube triangular ceiling fluorescent lamps, with 12 rows of intermittent escape belts, and 20 lamps