Surgical applications and clean room clean room classification today has been widely used in electronics, aerospace, machinery, chemical, pharmaceutical, food, medical, bio-engineering ...... walks of life. Moreover, with the national economy and the rapid development of scientific research institutions, clean room applications will be more extensive, and more important, according to cleanroom air flow type and intended use, and control of the main object classification. ⑴, clean room air flow pattern by dividing ① unidirectional flow (laminar flow) clean room, which was divided into vertical unidirectional flow clean room and horizontal unidirectional flow clean room. Figure XVI unidirectional flow Air flow pattern ② Non unidirectional flow (turbulence) cleanroom Figure seventeen non-unidirectional flow Air flow pattern ③ mixed flow chart eighteen mixed flow cleanroom air flow pattern ④ vector flow (diagonal flow ) Figure nineteen vector flow cleanroom air flow pattern ⑤ various flow characteristics, the creation of cleanliness, applications running costs and investment. ▲ purification principle unidirectional gas flow and squeeze the piston principle, the dust from one end to the other end of the squeezed out, with a clean replacement of contaminated air stream. Including vertical and horizontal unidirectional flow unidirectional flow. Vertical unidirectional flow is the flow at a constant speed (0.25m / s ~ 0.5m / s) from the ceiling of the air flow flowing floor type. This airflow can create 100, 10, 1, or higher level of cleanliness. But the initial investment is high, running costs are too high, the project area as much as possible to compress to a minimum, must be used in the site. Horizontal unidirectional airflow stream is a certain speed (0.3m / s ~ 0.5m / s) from a wall opposite the wall of the flow of air flow. The airflow can create 100 purification level. Its initial investment and running costs than vertical unidirectional flow pattern. ▲ non-unidirectional flow dilution air purification principle is the principle. General type of HEPA filter air outlet at the top; types have lower return air return air, return air and the top side of the lower back to the wind and so on. According to different air ventilation frequency to achieve different levels of purification, the initial investment and operating costs are also different. ▲ mixed gas flow is vertical unidirectional flow and non-flow two-way flow of air together constitute a flow pattern. This flow is characterized by the vertical unidirectional flow area of ??compression to a minimum, with a large area of ??a large area of ??alternative non-unidirectional flow unidirectional flow to facilitate initial investment and operating cost savings. ▲ give examples of different types of air volume air flow, cooling consumption, initial investment and operation of the specific consumption indicators in Table I. This index is based on electronic industry clean as the representative of specific data have reference value, but not easily Apply. Table a different level of clean plant clean air volume, the amount of investment in power indicator cold air flow type clean level (grade) air volume (m / s) (times / h) Cooling Consumption Indicator (W/m2) Investment Index (RMB / m2) Consumption Indicator (W/m2) vertical unidirectional flow 10 100> 0.25m / s 1300 ~ 1500 10000 ~ 13000 1.25 ~ 1.35 level 100> 0.3m / s 800 ~ 1000 5000 ~ 6000 0.9 ~ 1.0 Non- unidirectional flow 100 050 ~ 60 times / h 600 ~ 700 2800 ~ 3000 0.25 ~ 0.33 10000 25 ~ 30 times / h 500 ~ 600 2000 ~ 2200 0.22 ~ 0.26 100000 15 ~ 20 times / h 350 ~ 400 1400 ~ 1600 0.13 ~ 0.16 Note: The table air volume, unidirectional flow velocity in cross-section, said non-unidirectional flow in ventilation frequency representation. Table cold indicators are generally refers to the electronic industry clean. Table, the initial investment, including clean plant enclosure, frozen supply systems, air purification systems, excluding civil structures and automatic control of investments. The power consumption of the table refers to refrigeration systems and air conditioning system power consumption, excluding electric heating and electric power consumption of humidification. ⑵, by the use of the use or control of the main objects into ① industrial clean room: to control the dust as the main target. Used in electronics, aerospace, machinery, chemicals, chemical and pharmaceutical ....... ② biological clean room: to control bacteria (microorganisms) as the main target. For bio-pharmaceutical, medical, food, biotechnology, animal breeding, bio-security and other .......