01 September 2024

Step by Step: Cleanroom Gowning Requirements and Procedures

Cleanrooms are controlled environments designed to reduce the amount of debris and particles within the area. These controlled zones are meant to protect sensitive samples and electronic components, which need safeguarding even from small motes of dust, skin cells, hair and other tiny debris. Cleanrooms are often used in electronics manufacturing, food production, medical research and scientific laboratories.

Cleanroom Classifications and Requirements
The ISO 14644 has been the standard for cleanroom classifications and gowning requirements in the U.S. since 2001. This guideline is based on the 1963 FED-STD-209, Airborne Particulate Cleanliness Classes in Cleanrooms & Clean Zones standard created by the Institute of Environmental Science and Technology. ISO 14644 cleanroom gowning requirements are based on the highest allowed particle concentration in that zone.

Each classification of cleanrooms requires different gowns and protective gear, according to the ISO 14644-1 standard:

ISO 1 and 2: Coveralls, overboots, undergarments and gloves are recommended for this type of cleanroom. Masks, hoods and bouffant caps may be necessary depending on your application.
ISO 3: Hoods, coveralls, overboots, undergarments, facemasks, gloves and bouffant caps are recommended.
ISO 4: Hoods, coveralls, overboots, facemasks, gloves and bouffant caps are recommended.
ISO 5: Hoods, coveralls, overboots, facemasks, gloves and bouffant caps are recommended.
ISO 6: Coveralls, overboots and bouffant caps are recommended, while hoods, overshoes, undergarments, coats, facemasks and gloves may be necessary depending on the application.
ISO 7: Overshoes, coats and bouffant caps are recommended, and hoods, coveralls, overboots, undergarments, facemasks and gloves might be required as well for some tasks.
ISO 8: Coats and bouffant caps are recommended. You may need hoods, coveralls, overboots, overshoes, undergarments, facemasks and gloves for some applications.

How to Gown up for Cleanrooms
Properly gowning up for a cleanroom is vital to avoid cross-contaminating protective gear. You should always begin with proper hand-washing procedures before stepping over a tacky mat to remove debris. You will generally don protective gear from the head down. You’ll need to:

Put on overshoes or overboots.
Put on donning gloves, if required in your cleanroom process.
Put on a bouffant cap.
Move to the gowning area and apply the hood if necessary, taking care to only touch the inside of the hood.
Place a face mask correctly over the face.
Don booties and then goggles or a shield, if required.
Roll cleanroom gloves over your coverall sleeves.
Put on coveralls, being careful to touch only inside the neck area.
Walk over the tacky mat to remove any additional debris.

Doffing Cleanroom Gowns
After you’ve completed your tasks, you’ll need to doff all your gear from the bottom up, starting with the last item you put on. Place reusable items need in the laundry for cleaning and safely throw out disposable gear.