T&C (Testing & Commissioning) is the process of inspecting, testing, measuring and adjusting HVAC before the cleanroom enters service. Its aim is to verify operation against the design and maintain stable parameters such as airflow, temperature, humidity, pressure differentials and cleanliness.

  1. Pre-operation inspection

Before trial operation, inspect the complete system for correct and complete installation. Main items include AHUs, PAUs, fans, ducts, dampers, HEPA filters, air terminals, sensors and controls. Review design values as a reference for subsequent measurements and adjustments.

  1. Equipment trial operation

After installation checks, test individual equipment and then the complete system. Technicians check fans, motors, dampers, control valves and related equipment. Items such as fan rotation, noise, vibration, electrical current and equipment operation must be checked before system balancing.

  1. Measure and balance airflow

This is a key T&C step. Measure actual airflow at the AHU and supply, return and exhaust terminals and compare it with design values. Technicians then adjust dampers, fan speeds and related equipment to distribute airflow appropriately between areas. Accurate balancing improves conditioning and environmental control.

  1. Check cleanroom parameters

Once HVAC operation is stable, verify key cleanroom parameters:

  • Pressure differentials between areas
  • Temperature
  • Humidity
  • Airflow rates and velocities
  • Air cleanliness to project requirements

Control pressure differentials to maintain the intended airflow direction and limit cross-contamination between areas with different cleanliness requirements.

  1. Inspect HEPA filtration and controls

For cleanrooms, final filtration such as a HEPA filter must be checked for correct installation and integrity to project requirements. This helps maintain air quality before supply into the room. If connected to BMS/DDC, verify monitoring, controls, alarms and interlocked operation across the complete system.

  1. Adjust and correct deviations

Where measurements do not meet requirements, technicians investigate the cause and adjust the system. Parameters are retested to confirm compliance with operating requirements. This process reduces the risk of a completed installation failing to achieve the required performance or environmental conditions.

  1. Documentation & acceptance

After testing and adjustment, compile the results into the T&C records. These may include airflow, pressure differential, temperature and humidity readings, equipment checks and related results.

Summary

Cleanroom HVAC T&C involves more than trial operation: it is a comprehensive verification of actual performance. A complete T&C process helps HVAC operate stably, accurately and efficientlyand supports the cleanroom in meeting its technical requirements before use.