What is a Cleanroom
Cleanroom is a specially designed room in which the air within a certain space is free of micro-particles, harmful air, bacteria and other pollutants, and in which the temperature, cleanliness, indoor pressure, airflow speed and air distribution, noise and vibration, lighting and static electricity are controlled within a certain demand range. That is, regardless of how the external air conditions change, the room can maintain the original set requirements of cleanliness, temperature, humidity and pressure and other performance characteristics.
Cleanroom Components
The general components of a cleanroom include:
(1) Ceiling Plenum: including cleanroom ceiling tile, light fixture, the I-Beam or U-Beam air filters and gasketing.
(2) HVAC: including air showers, fan filter systems, blowers, etc.
(3) Wall Partition: Cleanroom windows and doors.
(4) Flooring: vinyl cleanroom flooring is either provided in either static dissipative or conductive levels of resistance. Available in either flooring sheets or flooring tiles
Cleanroom Classification
1. Turbulent Flow: The air enters the cleanroom from the air conditioning box through the air duct and the HEPA filter in the cleanroom, and is returned to the cleanroom by the cubicle walls or raised floor on both sides. The air flow is not linear but irregular and turbulent or swirling. This type is suitable for cleanrooms of class 1,000 to 100,000.
Its advantages: simple construction, system construction cost, easy expansion of the cleanroom, in some special places, can be used with a clean bench to improve the clean room level.
Disadvantages: The dust particles caused by turbulent flow are not easily discharged from the room and can easily contaminate the process products. In addition, if the system is stopped and reactivated, it often takes a long time to achieve the required cleanliness.
2. Laminar: Laminar airflow moves in a uniform linear pattern, with air entering the room from a filter with 100% coverage and returning to the room from a raised floor or partition on both sides, this type is suitable for use in environments with high cleanroom ratings, generally Class 1 to 100.
(1)Horizontal air is blown out from the filter in one direction and returned by the return air system on the opposite wall, with the dust being discharged outside with the wind direction.
Its Advantages: simple construction, stable in a short time after operation.
Its Disadvantages: Construction costs are higher than for the turbulent flow type, and it is not easy to expand the indoor space.
(2) Vertical laminar flow : The ceiling of the room is completely covered with ULPA filters and the air is blown from top to bottom to obtain a high degree of cleanliness.
Its Advantages: easy to manage, stable condition within a short period of time from the start of operation, not easily affected by working conditions or personnel.
Its Disadvantages: high construction costs, difficult to use space flexibly, the ceiling hanger takes up a lot of space, and it is troublesome to maintain and replace the filter.
3. Hybrid Cleanroom is a combination of turbulent flow and laminar flow type, which can provide local super clean air.
(1) Clean Tunnel: HEPA or ULPA filters are used to cover 100% of the process area or work area to increase the cleanliness level to 10 or more, which can save installation and operation costs. This type of tunnel is used to isolate the working area from the product and machine maintenance, so that the work and quality of the machine is not affected during maintenance. The clean tunnel has two other advantages: it is easy to expand flexibly and maintenance of equipment can be easily carried out in the maintenance area.
(2) Clean Tube: This encloses and decontaminates the automatic production line through which the product flows, raising the cleanliness level to over 100. Since the product is separated from the operator and the dust-generating environment, a small amount of air can be used to achieve a good cleanliness level, which saves energy and is ideal for automated production lines that do not require manual labour. It is suitable for the pharmaceutical, food and semiconductor industries.
(3) Partial cleanroom (Clean Spot): Cleanroom class 10,000~100,000 is used to improve the cleanliness of the product process area in the turbulent flow clean room to class 10~1000 or more for production; clean benches, clean booths and clean air cabinets are included in this category. There are also clean benches and clean booths.