Pressure drop is the hidden reason dust control under-performs. As filters load, hoses kink, or duct runs get longer, resistance rises and airflow under load falls. Less airflow means poorer capture, more airborne particulate, and higher exposure risk.

What is pressure drop?

Pressure drop is the resistance your system must overcome to move air through filters, hoses, and ducting. It is usually measured in pascals with a manometer. Free-air figures are irrelevant on site; only airflow under load matters. A steady rise in differential pressure across a filter usually means loading; a sudden change often points to damage, leaks, or a collapse in ducting.

Practical ways to manage pressure drop

• Shorten and straighten runs. Use the largest practical hose or duct diameter and minimise tight bends.
• Keep connections airtight. Tape or clamp every joint; even small leaks waste static pressure.
• Stage filtration. Use coarse pre-filters to protect fine filters or HEPA; swap pre-filters frequently.
• Add a cyclonic pre-separator for heavy debris to cut filter loading and maintain flow.
• Monitor differential pressure and set change-out triggers before airflow collapses.
• Specify equipment for the real system resistance. Check published under-load curves, not just free-airflow.
• Service seals and gaskets. A bypass around the filter ruins both capture and hygiene.
• Empty collection bins early. Overfilled bins increase resistance and risk carry-over.

On-site checks

• Record a clean-baseline: differential pressure across the filter and airflow at the hood or duct inlet.
• Re-check weekly. If DP rises but airflow holds, keep working; if airflow drops, change pre-filters.
• Use a simple anemometer to spot a 10–20% flow loss; investigate blockages or loaded media.
• Do a leak test with a smoke pencil around doors, lids, and hose joints.

On larger projects, teams often pair MAXVAC air scrubbers with sealed ducting and routine DP logging to keep airflow stable throughout the shift.

Practical takeaways

• Design for short, smooth, airtight runs.
• Protect fine filters with pre-filters or a cyclone.
• Measure DP and airflow under load; ignore free-air numbers.
• Service seals and empty bins early.

Pressure drop will always climb as filters load. Managing it proactively is the difference between compliant capture and visible dust drifting across site.