What Is A Clean Room?

A clean room is a filtered air environment required for a number of delicate manufacturing processes and some applications in the fields of biology and medicine.
Powerful filters remove pollutants, known as particulates, from the air. Clean rooms are classified according to the maximum size of particulate which is permitted and according to the number of particulates found per volume of air.

The human body naturally emits particulates so those entering all but the most primitive clean-room environment will be required to wear special clothing of some sort which, at the very least, will cover up almost all areas of visible skin. In high-grade clean rooms, a fully sealed 'space suit' with its own air supply will be required.

There are strict restrictions on activity within a clean room. Human bodies emit more particulates while moving than while standing still so people are normally be asked to be restrained in their movements. There are rules on what can be carried in and out of a clean room and certain items which are known to emit large numbers of particulates, such as food or pencils, are usually banned outright.