Sterile and Nonsterile Cleanroom Garments, Particle Emission Testing, Sterile and Nonsterile Gowning – Part 4: Aseptic Operational Aspects

This series of articles is intended to provide an overview of cleanroom gowning divided into four parts:

• Part 1: Materials and Components
• Part 2: Operational Aspects
• Part 3: Aseptic Facility Requirements
• Part 4: Aseptic Operational Aspects

Gowning for the Cleanroom

All operators must be trained and certified in proper donning and doffing techniques specific to the cleanroom classification and cleanroom manufacturing operations. Only approved cleanroom apparel is donned before entering the cleanroom. This apparel must be worn correctly to be effective in encapsulating contamination emanating from the cleanroom operator. Each company creates its gowning procedure for its cleanrooms based on the style of cleanroom garments, cleanroom classification and whether the cleanroom is sterile or non-sterile. Best practices in cleanroom management indicate that hanging laminated cleanroom gowning posters in the gown room will help ensure that all cleanroom operators are following the proper steps and gowning to their written protocol.

Non-sterile Gowning Procedure for ISO Class 3-5/Class B and Grade A Cleanrooms

Donning

Note that the following practices are recommended:

The cleanroom operator showers or bathes before coming to work

The company has a primary change where the operator changes out of street clothes into assigned polyester building pants and shirts

It is a best practice to remove primary garments if operators change out of street clothes into assigned polyester building pants and shirts, then proceed with non-sterile gowning.

There is a secondary change area where the operator will change - during donning do not let cleanroom garments touch the floor or walls of the gown room.

• Wash and dry hands.
• Enter non-sterile gowning area.
• Put on bouffant. Assure all hair is entrained under bouffant.
• Walk (at least three steps) over sticky mat to remove excess soil from shoes.
• Put on disposable shoe covers.
• Select appropriately sized coverall, hood and boots
• Put on donning gloves.
• Slide hood from cleanroom bag. Touch only the inside of the hood. Don hood, completely cover bouffant. Fit snuggly using vertical and horizontal snaps or ties in back of hood. Don disposable face mask or attach face veil to hood.
• To don coverall, grasp inside neck of coverall and slide coverall from sterile bag. Allow coverall to unfold. Unzip zipper to full length. Begin rolling coverall into a tube gathering the sleeves inside the roll. Gather up one leg. Place foot in one leg and pull up to thigh. Do the same with the other leg. Pull coverall up to waist. Begin unrolling top of coverall. Slide in one arm and roll coverall over back and shoulders (over drape of hood). Slide in other arm. Zip up coverall. Snap at collar and ankles (if required).
• To don boots, remove one boot from cleanroom bag by placing hand inside the boot top. Put on boot and step to the “clean” side of the gown area. Place hand inside the other boot top. Remove other boot from cleanroom bag. Put on boot and step to “clean” side of gown area. Pull up boot tops. Snap around calf area and snap to coverall leg (reusable cleanroom garments).
• Don safety glasses, goggles or shield.
• Remove donning gloves and put on new pair of gloves. Roll gloves over cuffs of coverall.
• It is a best practice to have a mirror near the exit to the change area with a drawing showing the required gowning, to allow the operator to confirm that the gowning is correctly in place. If a drawing or picture is used ensure that it is kept current with the relevant standard operating procedures (SOPs).

Doffing

Reverse the above procedure. Place disposable items in the covered trash receptacle. Place reusable cleanroom garments (coverall, hood and boots) in designated receptacle. Place goggles in separate, designated receptacle. Exit de-gowning area.

Gowning Procedure for Frocks in ISO Class 6-8/Class C-D Cleanroom

Donning

The gowning protocol for frocks is similar to the donning and doffing over coveralls. All hair is completely covered inside reusable or disposable bouffant including the ears. For longer hair it is suggested they have their hair tied up, e.g. ponytail. If required, a beard cover is used to cover all facial hair. Even if a cleanroom operator has a shaved head, a bouffant must be worn to prevent contamination from the scalp. The shoes are covered with reusable or disposable shoe covers. If static electricity is a concern, there are electrostatic discharge shoe covers. There are non-skid shoe covers to prevent slips, trips or falls in the cleanroom. If static electricity is a concern, ESD frocks are available. When donning a frock, the outside surface cannot touch the floor, walls or other operators in the gown room.

The frock is carefully removed from the cleanroom compatible, static dissipative bag by grabbing the inside surface of the fabric of the frock just below the collar on the back and allowed to unfold. The inside of the frock is folded back to protect the outside surface from contamination during donning. The right arm is placed inside the right sleeve and pulled to the full length of the sleeve. The left arm is placed inside the left sleeve and pulled to the full length of the sleeve. The frock is pulled over the back and shoulders and the zipper is pulled to the full length of the zipper and/or all snaps are snapped. Some cleanroom operations require gloves to be worn over the hands and wrist areas. The gloves overlap the wrist cuff area of the frock.

Doffing

When doffing the frock, it is recommended that the outside surface does not touch walls, floor or other operators. The frocks worn in ISO Class 6-8/Class C-D cleanrooms are often hung on hangers or hooks during the week. This area is preferably clean and under high efficiency particulate (HEPA) filters. The HEPA filtered air will remove some particles and fibers during storage. Place disposable items in a trash receptacle. Place reusable frock in a designated receptacle. Exit de-gowning area.

Gowning Certification

An environmental monitoring program is established, implemented and maintained to protect the integrity of the cleanroom, its products and processes. An essential element of an environmental monitoring program is personnel monitoring. Monitoring and auditing the cleanroom garment and gowning program assures that the documented procedures and protocols are understood, implemented at all levels within the cleanroom manufacturing process. The Code of Federal Regulations is vague but states : “There should be an established program to regularly assess or audit conformance of personnel to relevant aseptic manufacturing requirements.”

Typical monitoring of the personnel gowning program consists of training personnel on correct donning and doffing procedures per the company SOP’s part of their contamination control - aseptic training program. A written test and objective evidence of compliance to the company’s SOPs such as touch plates at selected sites. Typical sampling sites may include the forehead, chest, zipper, face mask, right and left forearms, fingers and behind right and left knees.

An audit of the environmental monitoring program provides documented and impartial evidence that the cleanroom management program is robust and reproducible. Tracking and trending this data will allow establishment of alert and action limits and show shifts in the program which can be addressed prior to compromising the entire cleanroom management program. There should also be practices in place to retrain and potentially remove operators if they exceed Acton levels.1^, 2^, 3^, 4^, 5^, 6^, 7^, 8^, 9^, 10^, 11^, 12^, 13^, 14^, 15^, 16^, 17^, 18^, 19^, 20^, 21^, 22^, 23^, 24^, 25^, 26^, 27^, 28

Bibliography

1. ISO-14644 – 1:2015 (Cleanrooms and associated controlled environments, Part 1 Classification of air cleanliness by particle concentration)
2. Eudralex Volume 4 GMP Guidelines Annex 1