A clean room is a room with air that meets federal standards for cleanliness set forth by the United States Federal Standard 209. The standard is called the Cleanroom and Work Station Requirements, Controlled Environments. It was originally published in 1963 but has been revised several times since then. Air can be contaminated by hair, skin, particles from machines and equipment, bacteria and cleaning agents. Clean rooms are required for a variety of purposes including scientific experiments and manufacturing of pharmaceuticals and some machines and electronic equipment.
Class 100 Standard
For a room to qualify as a class 100 clean room, there must be fewer than 100 particles that measure greater than 0.5 micrometers per cubic foot of air. This is the equivalent of an International Organization for Standardization or ISO class 5 rating.
In order to maintain clean air at a class 100 standard, the room must be cleaned regularly. High Efficiency Particulate Air, or HEPA, filters are used to maintain air cleanliness. In addition, according to the Coastwide Laboratories website, the room must be mopped and trash taken out daily. Wiping down the walls and vertical surfaces must be completed weekly. The tacky mats at the entrance to the room must be pulled every two hours.
According to the Fermi National Accelerator Laboratory website, individuals entering a class 100 clean room must step on a sticky mat prior to entering the dressing room to prevent bringing contaminants in on their shoes. A lab coat or coveralls should be worn and booties should be worn to cover shoes. Finally, hair should be secured in a hair net and approved gloves should be worn.
In addition to the dress code, individuals may not have food, drink or gum in the clean room. Make-up, hair products, lotion and fingernail polish is also prohibited and jewelry must be removed prior to entering the clean room. Paper and fabric towels are not to be used; rather the room should be equipped with a hand drier.