Powder charging into mixers, silos or IBCs can generate short, intense releases that overwhelm general ventilation. Effective control protects health, keeps the process compliant with COSHH, and prevents product loss and housekeeping headaches.

Plan the task and set up

Brief the team, check the safety data sheet, and choose a closed-transfer method wherever possible. Minimise drop height, use tight-fitting connections, and keep lids closed except when feeding. Stage bags and tools before opening to avoid delays with open product.

Capture at source

Fit flexible socks or sealed chutes to inlets to reduce free-fall and entrainment. Break bridging gently and feed steadily rather than dumping. If using a bag splitter, align the discharge to flow directly into the inlet to avoid cross-drafts. Antistatic matting and earthing reduce static lift-off for fine powders.

Control the air around the hatch

Create local negative pressure so any escape moves away from the breathing zone. Position an air scrubber close to the opening, ducted to pull across the work face. Select filtration suitable for the hazard (H14 for fine or carcinogenic respirable dusts) and verify airflow under load, not free-air figures. Units such as MAXVAC Dustblockers can be deployed to establish temporary negative pressure when paired with appropriate ducting.

Housekeeping and PPE

Never sweep or use compressed air. Clean spills with an industrial H-class vacuum and sealed bags. Keep surfaces lightly damped only where compatible with the material. Provide RPE (FFP3 or half mask with P3 filters) where monitoring indicates residual risk, and ensure face-fit testing.

Monitor and document

Use a particulate monitor near the work area to confirm controls are keeping peaks down. Keep short notes of controls used, readings, and filter maintenance. For silica or other substances with WELs (e.g., RCS at 0.1 mg/m³ per HSE EH40), record exposure checks under COSHH.

Practical takeaways

• Seal connections and minimise drop height to cut plume formation.
• Use local negative pressure with under-load airflow verified.
• Position capture so air moves away from the operator’s face.
• Vacuum only—no sweeping or blowing.
• Log monitoring results and maintain filters on schedule.

With simple design choices and disciplined set-up, powder charging becomes predictable and clean, reducing exposure, downtime, and cross-contamination.