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This page describes products and general use; it is not medical advice.
A cleanroom gown is the garment system worn over or instead of street clothing to keep the person from shedding particles and microorganisms into a controlled area. It is worn by personnel in drug manufacturing and other controlled areas. The grade table further down maps the garment elements to the grades in EU GMP Annex 1.
What is a cleanroom gown?
A cleanroom gown, also sold as cleanroom garments or a coverall or suit, is protective clothing that, in the words of the FDA aseptic processing guidance, should “provide a barrier between the body and exposed sterilized materials and prevent contamination from particles generated by, and microorganisms shed from, the body.” EU GMP Annex 1 (2022), paragraph 7.13, adds that the clothing “should minimize shedding of fibres or particles and retain particles shed by the body.”
In practice the “gown” is a set of components rather than one item. The FDA guidance names face-masks, hoods, beard and moustache covers, protective goggles and elastic gloves as common elements of gowns. Which elements are worn is set by each facility’s contamination control strategy.
How a cleanroom gown system is built
The regulator texts describe the system by what each element must cover, not by fabric. The components named in Annex 1 and the FDA guidance are:
- Suit or coverall: a single or two-piece trouser suit gathered at the wrists and with a high neck (grade C), or a general protective suit (grade D); under a sterilised suit in grade B, dedicated garments are worn.
- Headgear (hood or bouffant-style covering): must cover hair, beards and moustaches; in grade B it is sterile, encloses all hair including facial hair, and is tucked into the neck of the suit if separate.
- Mask and eye covering: a sterile facemask and sterile eye coverings such as goggles that cover and enclose all facial skin (grade B).
- Gloves: sterilised, non-powdered rubber or plastic gloves while donning, with sleeves tucked into a second pair of sterile gloves worn over the first (grade B).
- Footwear and shoe covers: sterilised footwear such as over-boots with trouser legs tucked inside (grade B); appropriately disinfected shoes or overshoes (grades C and D).
The FDA guidance also says an adequate barrier is created by overlapping gown components, for example gloves overlapping sleeves.
Types and variants by grade
EU GMP Annex 1 sets clothing by cleanroom grade (A to D), not by ISO class. Annex 1 paragraph 7.13 gives the following; see cleanroom classifications and ISO Class 7 requirements for how air-cleanliness classes are defined.
| Grade (Annex 1 para. 7.13) | Garment elements | Key difference |
|---|---|---|
| B (also access and interventions into A) | Dedicated garments under a sterilised suit; sterile headgear enclosing all hair; sterile facemask and sterile eye coverings; sterilised footwear such as over-boots; sterile gloves, double-gloved with sleeves tucked into the outer pair | Fully sterile, face and skin enclosed |
| C | Hair, beards and moustaches covered; single or two-piece trouser suit gathered at the wrists with a high neck; appropriately disinfected shoes or overshoes | Suit with high neck and gathered wrists; shedding minimised |
| D | Hair, beards and moustaches covered; a general protective suit; appropriately disinfected shoes or overshoes; measures to avoid ingress of contaminants from outside | General protective suit |
| C and D, higher-risk activities | Additional gowning including gloves and facemask may be required where the contamination control strategy defines a contamination risk | Set by the facility’s contamination control strategy |
The U.S. rule behind all of it is 21 CFR 211.28(a): personnel in drug manufacturing “shall wear clean clothing appropriate for the duties they perform,” with “head, face, hand, and arm coverings” worn as necessary to protect the product.
Gloves, shoe covers, masks and bouffant-style head covers
These are components of the system, not separate regulatory categories. Annex 1 requires sterile, non-powdered gloves in grade B and says gloves should be regularly disinfected during operations. The FDA guidance says gloves should be sanitized frequently. For headgear, the requirement is coverage: all hair, and for grade B also facial hair, enclosed.
How to choose: criteria the regulators state
Regulators state criteria a garment programme is judged against:
- Low shedding and particle retention: Annex 1 says particle shedding and retention efficiency are assessed during garment qualification.
- Sterile where the grade requires it: the FDA guidance recommends gowns that are sterilized and nonshedding, and that cover skin and hair.
- Appropriate size at each entry: operators entering grade B or A gown into clean, sterilised garments of an appropriate size at each entry.
- Packaging that avoids contact: garments are packed and folded so operators can don them without touching the outer surface or letting it touch the floor.
- Defined wear period: the maximum period a sterilised gown may be worn during a shift is defined in garment qualification.
Safe use and handling basics
- Gown in change rooms of the appropriate grade. For grades B and C, outdoor clothing including socks is not brought into the changing rooms; facility trouser suits covering the full length of arms and legs and facility socks are worn before entry to the change rooms (Annex 1 para. 7.14).
- Change garments and gloves immediately if damaged (Annex 1 para. 7.16; the FDA guidance says the same of a torn or defective element).
- Reusable clothing is laundered in a segregated laundry using a qualified process that does not damage it or add fibres or particles (Annex 1 para. 7.17).
- Gowning is qualified by microbiological surface sampling of several locations, such as glove fingers, facemask, forearm and chest, and requalified periodically. The FDA guidance notes annual requalification is normally sufficient for automated operations where personnel involvement is minimized and monitoring data indicate environmental control.
The donning sequence itself is covered in the cleanroom gowning procedure, and a facility walk-through in the cleanroom checklist. For how a general cleanroom lab is organised, see clean room lab.
Common mistakes
- Continuing to work with a torn sleeve, glove or hood instead of changing it at once.
- Letting the outer surface of a sterile garment touch the floor or the operator while donning.
- Gloves that are not sanitized frequently during operations.
- Bringing outdoor clothing, including socks, into change rooms leading to grade B and C areas.
- Gaps between components: the FDA guidance expects overlap, for example gloves over sleeves, so no skin is exposed.
FAQ
What is the difference between a cleanroom gown and a surgical gown?
A cleanroom gown protects the controlled area and product from the wearer, by limiting shedding and retaining shed particles (Annex 1 para. 7.13). A surgical gown is a different device; see what is a surgical gown.
Do cleanroom gloves have to be sterile?
In grade B and for interventions into grade A, Annex 1 requires sterilised, non-powdered rubber or plastic gloves while donning, with a second sterile pair worn over the first. Grades C and D do not require this by default, but extra gloves and a facemask may be required for higher-risk activities defined by the contamination control strategy.
Are shoe covers required in a cleanroom?
Annex 1 calls for sterilised footwear such as over-boots in grade B, and appropriately disinfected shoes or overshoes in grades C and D.
Does a cleanroom mask or hair cover have to cover facial hair?
Yes. Annex 1 requires hair, beards and moustaches to be covered in grades C and D, and in grade B the sterile headgear encloses all hair including facial hair.
How often is a gown replaced?
Annex 1 says operators entering grade B or A gown into clean, sterilised garments at each entry, and the maximum wear period during a shift is defined in garment qualification. Damaged garments are changed immediately.
Sources
- European Commission, EudraLex Volume 4, Annex 1 Manufacture of Sterile Medicinal Products (2022), paragraphs 7.11 to 7.17: https://health.ec.europa.eu/system/files/2022-08/20220825_gmp-an1_en_0.pdf. Date checked: 2026-10-30.
- U.S. FDA, Guidance for Industry: Sterile Drug Products Produced by Aseptic Processing, Current Good Manufacturing Practice (September 2004), section V.A, non-binding guidance: https://www.fda.gov/media/71026/download. Date checked: 2026-10-30.
- 21 CFR 211.28(a), Personnel responsibilities: https://www.law.cornell.edu/cfr/text/21/211.28. Date checked: 2026-10-30.
