Construction sites need enough airflow for capture and air changes, but neighbours and hearing limits still apply. The aim is not silence; it is controlled noise with verified dust control.

Understand the trade-off

Airflow needs energy. Faster fans and tighter ducting raise both airflow and noise. Larger impellers turning slower can move the same air more quietly. What matters is meeting your target capture velocity or air changes per hour with acceptable decibels at the working position.

Practical controls to reduce noise without losing performance

• Upsize the unit and run at lower speed to cut tonal noise while keeping airflow under load.
• Place scrubbers outside the work area and duct in/out; seal penetrations to avoid leaks.
• Use larger, smoother ducting and gentle bends; every kink adds resistance and noise.
• Add short lined sections or silencer cuffs on the discharge where feasible.
• Decouple vibration with anti-vibration feet and avoid mounting on resonant panels.
• Keep filters clean and impellers true; worn bearings and loaded filters are noisy and inefficient.
• Schedule high-flow tasks when fewer people are present; rotate staff and provide hearing protection where required.
• Use variable speed control to trim just enough flow to meet air change or capture targets.

Verify both noise and airflow

• Measure airflow under load at the hood or duct end; do not rely on free-air specs.
• Calculate air changes per hour and log them against noise readings at ear height.
• If noise is high, first improve ducting and placement, then reduce speed in small steps while re-checking capture.

Many sites use MAXVAC negative air machines with variable speed to tune flow to the task while keeping noise within local constraints.

Practical takeaways

• Design ducting for low resistance before chasing acoustic fixes.
• Run larger equipment slower for quieter airflow.
• Measure ACH and dB together; adjust speed, placement, or ducting accordingly.
• Maintain bearings and filters to prevent avoidable noise.

By treating airflow and noise as a single system, you can keep airborne particulate controlled and the working environment tolerable.