In food plants, dust is both a hygiene risk and a worker exposure issue. Flour, sugar and spice dust can contaminate product, trigger allergens and attract pests. A simple, well-placed monitoring setup helps prevent contamination while supporting COSHH duties and audit readiness.

Set objectives and zones

Start with HACCP: where can dust contaminate product or packaging? Define critical and sensitive zones (e.g., bag tipping, mixers, conveyors, weigh/pack, high-care). Set practical alert levels for housekeeping and process checks. For workforce exposure, remember HSE sets WELs for substances such as flour dust (inhalable). Use area PM as an operational indicator; use personal sampling for exposure assessment.

Choose monitoring that fits food environments

• Use real-time particulate monitors showing PM10/PM2.5/PM1 to spot spikes and trends. Mount at breathing height away from direct jets and ingredient streams.
• Log baseline data during clean conditions, then during production, changeovers and dry cleaning. Review weekly against deviations.
• Add point sensors in enclosed transfer points to trigger local alarms for blockages or extraction failure.

Link readings to immediate actions

• On a spike: pause the task, check LEV hoods and duct dampers, inspect filter differential pressure, and confirm make-up air paths.
• If controls are degraded: change pre-filters, reseat gaskets, and schedule main filter change in a segregated, clean-down area.
• Clean locally with an industrial H-Class vacuum with a sealed waste system; avoid sweeping or compressed air which redisperse allergens.

Integrate controls using the three-layer approach

1) Capture at source

• Enclose transfers, fit close-capture LEV to bag tipping and sack slitters, and adjust process speeds to minimise bursts.
• Use food-safe ducting and smooth transitions; keep hoods close without impeding sanitation.

2) Capture in the air

• Use air scrubbers or negative air machines with a full filtration chain and H14 final stage in sensitive areas; position so airflow draws away from open product.
• Verify airflow under load and reconsider placement after layout changes.

3) Capture on surfaces

• Adopt dry cleaning where moisture is a hazard; vacuum high to low, equipment to floor, then dispose of waste sealed.
• Schedule filter maintenance outside production; document lot/date to support traceability.

Verification and records

Trend PM data, LEV checks, and cleaning sign-off together. Investigate persistent hotspots with smoke tests and adjust hoods or barriers. Keep concise records for audits (BRCGS, retailer standards) and for COSHH review.

Practical takeaways

• Place PM monitors at breathing height in tipping, mixing and packing zones.
• Use PM alerts to trigger LEV checks and targeted vacuum clean-ups, not sweeping.
• Maintain a filtration chain with H14 in sensitive areas; change pre-filters early.
• Document spikes, actions and outcomes to strengthen HACCP verification.

Focused monitoring turns dust from a hidden contamination route into a controlled variable, improving product integrity and worker protection without slowing production.