Good ducting turns a decent extractor into a reliable dust control system. Poor ducting wastes airflow, clogs, and leaks dust back into the workspace. These fundamentals will help you lay out, build, and maintain ducting that works on site and in workshops.

Plan the system, then the route

List your sources, approximate flow needs, and which will run together. Prioritise the tasks that drive your peak demand. Route ducting along the shortest path with the fewest bends. Keep extractors close to high-resistance tools and avoid long runs of flexible hose.

Use smooth, open, gentle paths

Prefer smooth-bore rigid duct for mains and keep flexible hose to short drops for connection and movement. Use large-radius elbows or swept bends; two gentle bends usually beat a tight 90-degree elbow. Avoid sudden reductions and right-angle tees; use wye branches with a shallow entry to reduce turbulence and pressure loss.

Seal, support, and earth

Every leak costs capture. Seal joints with appropriate clamps or gasketed fittings; tape alone is a last resort. Support ducting to prevent sags where dust can settle. Where applicable, earth metal ducting and use antistatic hose to reduce static build-up and nuisance shocks.

Balance and prove

Fit blast gates on branches to balance flow and shut off unused drops. Install simple gauges (e.g. differential pressure across filters) so operators know when maintenance is due. Prove performance with smoke tests and, where exposure is a concern, confirm with a particulate monitor.

Maintenance and compliance

Keep filters and separators serviced to maintain airflow under load. Inspect ducting for wear, leaks, and build-up. Under COSHH, LEV requires thorough examination and testing at least every 14 months; design access points now so inspections and cleaning are straightforward.

Practical takeaways

• Short, smooth, and gentle: minimise hose, avoid tight elbows, and use wye branches.
• Seal and support all joints; prevent sags and settling.
• Balance with blast gates and install simple pressure gauges.
• Design for inspection and cleaning from day one.
• Verify performance on the floor, not on paper, and maintain it.

Solid ducting design underpins the three-layer approach: strong source capture, cleaner ambient air, and easier housekeeping with an industrial vacuum.