IEST-RP-CC003 explained: how to evaluate a cleanroom garment system

IEST-RP-CC003The Institute of Environmental Sciences and Technology recommended practice on garment system considerations for cleanrooms, covering fabric, construction, testing and processing., Garment System Considerations for Cleanrooms and Other Controlled Environments, is the recommended practice published by the Institute of Environmental Sciences and Technology. It is not a regulation. It is the most widely used reference for deciding whether a garment is fit for a cleanroom, and many pharma and electronics specifications cite it.

The central idea is that a garment is a system: the fabric, the way it is cut and sewn, how it is laundered and sterilised, and how people wear it all decide how much contamination escapes.

1. Fabric

The recommended practice looks at the properties that matter in use:

• Particle barrier and filtration. How well the fabric holds back particles released by the body. Tightly woven continuous filament polyester performs well here.
• Particle sheddingRelease of particles and fibres from a garment during wear. Low shedding is a core requirement for every cleanroom garment.. Spun yarns and cotton release fibres. Continuous filament yarns do not.
• Air permeability and comfort. A fabric that stops everything but traps heat makes operators sweat, and sweat carries particles. Balance matters.
• Electrostatic properties. Carbon grid or stripe yarns let charge dissipate, which matters for ESDElectrostatic discharge: a sudden release of static electricity that can damage electronic parts or ignite flammable vapours. sensitive work and for keeping particles from clinging to garments.

2. Construction

Construction is where a good fabric can be let down. Look for:

• Seams that are bound or covered so no raw edge is exposed.
• An enclosed zip with a storm flap.
• Knitted or elasticated cuffs and ankles that seal against gloves and booties.
• No external pockets, pleats or loose trims that trap particles.
• Thread and zips made from low shedding, autoclave compatible materials.

3. Testing

IEST-RP-CC003 describes test methods that let you compare garments on evidence:

• Helmke drum testA test that tumbles a garment in a rotating drum while counting released particles. Described in IEST-RP-CC003 and used to compare garments and track them over their life.. The garment tumbles in a drum while a particle counter samples the air. It gives a repeatable particle shedding figure for a whole garment, not just a fabric swatch, and is often used to track garments over their life.
• Body box testing. A person in the garment moves through set exercises inside an enclosure while particles are counted. It reflects real use, including the effect of fit and construction.
• Fabric tests for filtration, air permeability and electrostatic performance.

Ask suppliers which tests they ran, on which garment, and after how many processing cycles. A result on a new garment tells you less than a result after 25 or 50 cycles.

4. Processing and garment life

Laundering and sterilisation gradually change the fabric. The recommended practice expects a defined processing method and a planned end of life based on test results and inspection, not on appearance alone. That is why cycle tracking and periodic testing are part of a good garment programme.

How to use it when you compare suppliers

1. Ask for the fabric data sheet with filtration, air permeability and electrostatic results.
2. Ask how the garment is constructed, with photos of the seams, zip and cuffs.
3. Ask for particle shedding data and the test method used.
4. Ask for the design cycle life and how garments are identified for cycle tracking.
5. Ask for a sample, and run your own gowning and comfort trial.

Related reading

• Antistatic cleanroom garments explained
• EN 1149-5 and ANSI/ESD S20.20 compared
• Cleanroom glossary