2.5 Equipment & Materials in Classified Areas Under Dynamic Conditions

2.5 Equipment & Materials in Classified Areas Under Dynamic Conditions

A cleanroom that passes certification while it is empty proves very little. People, carts, pumps, printers and supply bags all shed particles and disturb airflow. USP <797> therefore judges facilities under dynamic operating conditions, meaning normal compounding with the usual number of people present and equipment running. This section covers how to choose and place equipment and materials so the ISO classification holds up during actual work.

What "dynamic operating conditions" means for testing

Recording headcount matters because a room certified with two people present may fail with five. If the SOPs allow four people in the buffer room at once, certify with at least four.

Rules for what may enter a classified area or SCA

USP <797> Section 4.5 sets the baseline:

• Only what is necessary. Only furniture, equipment and materials needed for compounding are allowed, and they should be low-shedding and easy to clean and disinfect. Their number, design, location and installation must not harm air quality and must allow effective cleaning.
• No cardboard. Shipping cartons and any corrugated or uncoated cardboard are not allowed in a classified area or SCA. Items are unpacked outside and wiped before entry (see 7.3).
• Carts. Carts are made of nonporous materials with cleanable casters and wheels. In a cleanroom suite, a cart is not moved from the dirty side to the clean side of the anteroom unless the whole cart, casters included, is cleaned and disinfected.
• Keep equipment in place. Equipment used in classified areas stays there except for calibration, servicing or cleaning. If it leaves, it is cleaned and wiped with sterile 70% IPA or a suitable disinfectant before it returns.
• Patient-care items. Materials exposed in patient care or treatment areas may not enter anterooms, buffer rooms or SCAs unless thoroughly cleaned and disinfected.
• Ledges and surfaces. Any overhang or ledge must be easy to clean. Classified-area surfaces are smooth, impervious and non-shedding, and wood or other porous materials are avoided.

Equipment inside the PEC

The ISO Class 5 space is the most sensitive, so equipment placement there is verified with smoke:

1. Only equipment needed for the task goes into the PEC.
2. Its placement is verified with a dynamic airflow smoke pattern test to show minimal disruption of airflow, and the test is repeated if the equipment is moved.
3. Laminar airflow systems (LAFS) must be out of traffic and away from room air currents, and they are smoke-tested initially and at least every 6 months. The test shows that the unit is placed correctly and that compounders know how to keep first air on the direct compounding area.
4. Robotic enclosures, whether used as the PEC or placed inside one, are smoke-tested initially and at least every 6 months. The test must show proper integration, no turbulence or reflux at critical sites, no entry of room air where sterile items are exposed, and that every process can be done without contaminating the direct compounding area.
5. RABS (CAI or CACI): the recovery time needed after the transfer chamber is opened must be documented, usually by the manufacturer, and SOPs must build that wait into operations.

Nonsterile work in or near sterile space

• Presterilization procedures. For Category 2 or 3 CSPs made from nonsterile components, weighing and mixing happen in ISO Class 8 or better air (for example the anteroom or buffer room). The work is done inside a single-use containment glove bag, a containment ventilated enclosure (CVE), a BSC or a CACI. A CVE, BSC or CACI used this way is certified at least every 6 months, and the work must not degrade the room's classification during dynamic certification.
• Airborne chemical particles. Any step that could release airborne particles, such as weighing APIs, must be assessed to decide whether it needs a PEC or a closed processing device, and the assessment is documented.
• Sterile and nonsterile PECs in one room. They belong in separate rooms, unless the nonsterile PEC is effective enough that the room stays ISO Class 7. If they share a room, they must be at least 1 meter apart, and no particle-generating work is done while sterile compounding is under way.

Temperature and humidity

USP <797> says the cleanroom suite should be kept at 20 °C or cooler and 60% relative humidity or below. Cooler, drier air keeps gowned staff from sweating and shedding, and it discourages microbial growth. USP's commentary treats these figures as recommendations. The facility sets its own limits and confirms them through its environmental monitoring results. Temperature and humidity are monitored on compounding days and reviewed as the SOPs describe. The monitoring devices are calibrated or verified as the manufacturer recommends, or every 12 months if the manufacturer gives no interval. For an SCA, USP's FAQ says the cleanroom figures are reasonable guidance, but any drug storage rules must also be met.

Exam traps

• A room that passes at rest but fails dynamic testing is not certified.
• Taking a cardboard case into the buffer room "just for a minute" is not allowed.
• Moving the ACD pump to the other side of the hood requires a new smoke test.
• Weighing nonsterile powder on an open bench in the anteroom is not allowed; it needs containment.