Differences Between Air Shower, Buffer Room, and Air Lock

An air shower, also known as an air shower room, air shower door, air shower unit, air blow-down room, dust shower room, air disinfection room, or airshower, is primarily composed of several major components: a fan, a HEPA filter, a control circuit, and a cabinet. The air shower is essential purification equipment at the entrance of a cleanroom. Its main function is to remove dust from the human body through blowing, thereby achieving purification. Provided the airflow is sufficient, it can remove most of the dust from a person's body. Of course, this is only one of its functions.

The most important function of the air shower is to act as an effective barrier between the cleanroom and the outside environment. The main difference between an air shower, a buffer room, and an air lock is that the air shower has the function of purification filtration and air blowing.

Buffer Room: The structure of a buffer room is roughly the same as that of an air shower, mainly reflected in the construction of the inner and outer cabinets and the dimensional space. Its main difference from the air shower is the lack of the air blow-down function. Consequently, it primarily lacks the main control system, purification filter, and fan found in an air shower. Its main function is to have electronic interlocking. The buffer room is the necessary passage for personnel or materials entering the clean area from the non-clean area. Its air pressure gradients incrementally from the outside (non-clean area) to the inside (clean area). The buffer room serves two purposes: one is to prevent airflow from the non-clean area from directly entering the clean area; having a buffer room significantly reduces this possibility.

The second is that when personnel or materials enter the clean area from the non-clean area, they have a "holding" period in the buffer room for self-cleaning (mainly for materials), to avoid contaminating the clean area after entry.

Function of the Air Lock: The air lock is set up to maintain the air cleanliness level and positive pressure control of the cleanroom. Air locks are typically installed between two identical clean areas of different cleanliness levels, or between a clean area and a non-clean area.

They prevent cross-contamination between different environments. The air lock maintains negative pressure relative to the connected functional rooms and is fully exhausted. The air lock has two doors that cannot be opened simultaneously, aiming to isolate the air from two different clean environments and prevent contaminated air from entering the clean area. Air locks can be with or without supply air. Air locks for stringent biological cleanrooms generally have purified air conditioning supply air.

Difference Between Air Lock and Buffer Room: Common points: Both air locks and buffer rooms are intended to separate two areas, preventing direct connection between them; they both have supply and exhaust air, are fully exhausted, their doors should be interlocked (cannot be opened simultaneously), and both have self-cleaning functions.

Difference: An air lock typically separates two different clean areas. It maintains negative pressure relative to both areas. Its main function is to prevent cross-contamination between the two clean areas, acting bidirectionally.

A buffer room is located between a non-clean area and a clean area. It maintains positive pressure relative to the non-clean area and negative pressure relative to the clean area. Its main function is to prevent contamination of the clean area by the non-clean area, acting unidirectionally.