Cleanroom Design and Construction
The design and construction of cleanrooms are comprehensively planned around core parameters such as production processes, cleanliness classes, temperature and humidity, pressure differentials, and air change rates. Adhering to standards like GMP and ISO 14644, the design ensures space cleanliness, controllable airflow, and contamination isolation, while balancing construction efficiency, operational costs, and safety.
During the preliminary design phase, the project's purpose and cleanliness standards are defined based on specific application scenarios—such as pharmaceuticals, medical devices, food processing, PCR laboratories, or electronics manufacturing. Corresponding cleanliness classes are established, and zoning for clean and dirty areas is planned alongside personnel and material flow paths. Independent channels are designated for personnel and materials, incorporating isolation facilities like airlocks, air showers, and pass-through boxes to prevent cross-contamination. The HVAC system is central to the cleanroom; air change rates are calculated based on room volume and class, utilizing components such as Air Handling Units (AHUs), HEPA supply diffusers, Fan Filter Units (FFUs), and Venturi valves to maintain stable indoor pressure and prevent the infiltration of unpurified outdoor air. An integrated automatic control system monitors parameters including temperature, humidity, pressure differentials, and airborne particles. The enclosure structure utilizes airtight, corrosion-resistant, and dust-resistant color-coated steel panels; joints between wall and ceiling panels are sealed, and coved corners are used to minimize dust accumulation. Cleanroom doors, observation windows, and pass-through boxes are equipped with industrial interlocking mechanisms to prevent pressure imbalances caused by opening doors. Electrical systems—including power distribution, lighting, emergency power, and grounding—are planned concurrently to meet explosion-proof and anti-static requirements for clean zones, with ozone disinfection systems added for specialized applications.
The construction phase follows a sequence of prioritizing mechanical rooms before clean zones and utility piping before enclosure structures. Site cleanliness is strictly managed prior to construction to prevent dust contamination from civil works. Following the prefabrication and embedding of electromechanical piping, enclosure panels are assembled; joints between wall and ceiling panels are sealed with adhesive, and all concave corners feature coved transitions. Cleanroom equipment—such as air showers, pass-through boxes, and cleanroom doors—is installed concurrently. The HVAC system undergoes duct fabrication and airtightness testing, followed by the installation of units, valves, and terminal HEPA filters; finally, the ductwork undergoes sectional purging to remove internal impurities. Once installation is complete, the system enters the commissioning phase, involving the sequential adjustment and verification of airflow rates, air change rates, room pressure differentials, and temperature and humidity levels. After the system stabilizes, cleanliness performance testing is conducted—covering parameters such as airborne particles, settling bacteria, airborne microbes, and noise levels—and formal acceptance is organized only after all design specifications are met.
Following final acceptance, a complete set of as-built drawings, equipment documentation, and operation and maintenance manuals must be handed over, and operations and maintenance training provided to the end-user. The completion of construction does not mark the end of the project; long-term performance of the cleanroom relies on the periodic replacement of FFU filter elements and HEPA filters, continuous monitoring of cleanliness parameters, and the rigorous management of personnel access.