According to American Federal Standard, a clean room is "a room in which the quantity of particles floating in the air , when necessary, the temperature, humidity, and pressure, can be controlled, the main objective of the dust in a given room is determined according to the requirements of the products to be handled in the room.

(A) Cleanliness and the number of ventilation cycles. The cleanliness of the room depends upon the number of ventilation cycles performed per unit time. the structure should be contrived so that the air flow is distrubed as little as possible and due care should be taken to prevent the accumulation of dust on surfaces anywhere in the clean room. In order to maintain the cleanliness of the room, the inflow of contaminating particles from outsid must be prevented. To obtain the required room pressure, outside air of

apprepriate quality and quantity is necessary.

(B) Material and anxiliary equipment for clean room Material that is not suscepitable to caracking or the adherence of particles and which creates little dust is employed for the ceiling, walls and floor. when necessary, such auxiliary equipment as air showers in the entrances and pass-boxes in the walls must be installed.

(C) Control of personnel and materials Personnel, and materials brought, are the main sources of dust in clean rooms, so adequate controls must be adopted. For example, all personnel should be made to pass through air showers and change into dust-free clothes before entering clean rooms.

(D) Other facilitiesAccording to the work to be performed water supply and drainage facilities and eletricity and gas supplies may be necessary. There facilities and related equipment should be easy to use should be desighed in such a way as to avoid and deterionation in the air cleaning performace of the system. Because Clean Room is completely closed, measures to take in case of emergencies such as a fire, a power failure, must be fully considered.

(E) The first decision you'll face is choosing between a manufacture modular cleanroom and a conventional construction cleanroom. A manufactured modular cleanroom is custom built at the vendor's factory and assembled at your facility, while a conventional construction cleanroom is built from the ground up at your site.

(F) To determine usage requirements, estimate how many people will work in the cleanroom and how often they will enter and exit. The size and amount of furniture and equipment must also be considered. These requirement will help you to determine the size of cleanroom you need.