by Rebekah Fuller, Editor at IQS
Sounds like a party doesn’t it? But I’m talking about the seriously controlled environments of clean rooms used by scientists and manufacturers in the fields of micro technology and biochemistry. Working on smaller and smaller scales means that specks of dust and other particles are big, boulder-size deals, plus bacteria, static electricity and humidity are concerns as well. That’s why workers need to suit up before entering any clean room environment – this is where the “bunny suit” comes in, and I’m not talking about rabbits or risque women … it looks like a light-duty astronaut suit.
Clean rooms image courtesy of American Cleanrooms.
The common term for a clean room suit is a bunny suit, and the process of dressing for entry into a clean room is called gowning; after all, they may be going into a “ballroom” – the largest of all clean rooms. And who wants to attend a ball without a “buddy” … or a date as the kids call it. Standard operating procedure for clean rooms should include a buddy system, especially on university campuses where students are putting to the test their clean room orientation courses, as chemical hazards, burning and electrocution are some of the risks associated with work in clean rooms. The University of Louisville’s Cleanroom Buddy Policy states, “Do not do any wet chemistry, photolithography, or furnace work without a buddy in the cleanroom with you!”
It’s always good to have a clean room buddy who has your back if something goes wrong, such as the research scientist team of Phil and Lem in ABC’s new satirical office comedy, “Better Off Ted”, about the research and development department of a global, morally questionable corporation. When Phil was ordered to be cryogenically frozen for testing purposes, who was there for him when he thawed? They ensure each other’s safety – like when they are asked to develop pumpkins that double as weapons of mass destruction.
The fictional work that Lem and Phil do is set up for hilarity to ensue, and seems like they could use a HAZMAT suit instead of a clean room suit. As the most important of all clean room supplies, the suit – not intended to protect the wearer from hazardous materials – protects the sensitive objects and substances with which the researchers are working. In this progressively nanoscale technology era, a long list of industries and products require clean rooms of certain levels: chemical, computer, biomedical, electronics & microelectronics, disc memory, small parts machining and assembly, packaging, pharmaceutical, photographic, aerospace, nuclear, optical, circuitry, hybrid, etc.
For example, clean rooms are essential for Intel’s microprocessor manufacturing. This component is no bigger than a dime and consists of millions of microscopic transistors. Even one grain of salt could spell Armageddon for the tiny computer chip. A clean room’s air is constantly filtered to ensure the least number of particles. The cleanest clean room is called a Class One, allowing no more than one speck of dust per cubic foot. There are also Class 100s, Class 1,000s, Class 10,000s and Class 100,000s. The focus is usually on eliminating particles 0.5 microns or larger, though some go smaller than that. Just to give you an idea, a human hair on average has a 100-micron diameter, and humans are known to shed dead skin cells at 100,000 particles per minute simply standing still. No wonder why a clean room staff has to suit up – double gloves, double booties, helmet and all – before taking one step inside their work environment. Suiting up for the amateur could take 30 to 40 minutes, but the pros at Intel have it down to five.
Clean room design varies in size, material and level of cleanliness depending on the type of application. Microelectronics, pharmaceuticals, or circuitry manufacturing use the warehouse-size ballroom clean rooms with high cleanliness classification, while small parts manufacturers may not need as low a particle count and will utilize portable clean rooms for specialized assembly. Clean rooms can come in modular and softwall designs for versatility and flexibility, and other supplies include adhesive floor mats and tacky rollers to grab and trap particles from shoes and other surfaces.