GMP‑compliant cleanrooms are designed to meet the specific requirements of pharmaceutical manufacturers and the unique characteristics of their products. We have identified common deficiencies in such facilities. If these issues remain unresolved, the pharmaceutical plant may fail GMP compliance inspections. In such cases, the company must undertake corrective measures and optimize its cleanroom operations.

1. The GMP cleanroom design is inadequate.

The reasons for inadequate cleanroom design include: first, in workshops with relatively low cleanliness requirements, some contractors win bids with lower prices but cut corners during construction, resulting in substandard cleanliness; second, after construction is completed, clients introduce additional requirements and expand the cleanroom area. By addressing these issues proactively during the design phase and tailoring the cleanroom project to the client’s actual needs, we can prevent such problems from arising.

2. Insufficient design and commissioning of the return air ducts

The primary reasons for poor design and commissioning of the main return air duct are limited space, failure to adopt a “top-supply, side-return” configuration, or an insufficient number of return air outlets. Another factor is improper adjustment of the supply air outlets, leading to excessive resistance at the return air inlets and resulting in a return airflow rate that falls short of the supply airflow rate—conditions that can easily compromise cleanliness levels. Furthermore, the height of the return air outlets above the floor significantly impacts overall cleanliness.

3. Air conditioning system piping has not been cleaned.

Air-conditioning ductwork, particularly supply and return air ducts, if left uncleaned after being flushed, can lead to secondary contamination of the ventilation system and filters. During the renovation and optimization of GMP‑compliant cleanrooms, cleaning should be carried out concurrently with construction; following cleaning, the ductwork should be sealed with plastic sheeting to prevent recontamination.

4. Insufficient air-conditioning self-cleaning time prior to testing

Turn on the air conditioning in the GMP cleanroom and begin testing after it has been running normally for 30 minutes. If the operating time is too short, the cleanliness level may easily fail to meet the required standards.

5. Use low-end equipment

If the cleanliness level is greater than or equal to 100,000,三级 filtration must be employed. Some workshops use low‑power ventilation systems or filters, which can easily result in non‑compliant cleanliness levels.

When pharmaceutical companies encounter these issues, dirty and poorly maintained production facilities with low productivity can easily result in failing a surprise inspection. At present, this workshop no longer meets the requirements of a GMP‑compliant cleanroom. It is recommended that the company undertake renovation and optimization of the facility.

How can the impact on GMP cleanrooms be avoided?

1. Install local exhaust ventilation systems at equipment that generates hazardous substances to discharge these substances outdoors. Local exhaust ventilation systems shall be provided as separate units.

2. A medium-efficiency filter is used, featuring a simple structure and convenient maintenance.

3. It employs a closed-type valve, offering excellent sealing performance, a complex structure, and convenient operation and maintenance.

4. Implement an automatic smoke-control system. Install mechanical smoke-control equipment in areas such as rooms, workshops, and evacuation corridors.