Cleanrooms demand tight particulate control to protect product quality and operator safety. The essentials are stable pressure cascades, effective capture at process points, verified HEPA/ULPA filtration, and disciplined behaviours that prevent re‑contamination.

Define the risks and pressure strategy

Map each process step: where particles are generated, how materials move, and which rooms need positive or negative pressure. Keep cleaner areas at slightly higher pressure than adjacent spaces to drive airflow outwards, and isolate high-dust tasks in dedicated rooms or enclosures.

Capture at source for dusty processes

• Weighing and dispensing: use purpose-built powder enclosures or local exhaust ventilation (LEV) with stable, low-turbulence capture.
• Machining, deburring, or additive manufacturing post-processing: fit shrouds and LEV on tools, and choose slower, cooler cuts to limit emission.
• Material transfers: enclose transfers, minimise drop heights, and pre-wipe containers before they enter cleaner zones.

Air filtration and airflow under load

Specify HEPA H14 where fine particulate or critical quality is involved; ULPA may be required for the most sensitive steps. Ensure fan units deliver required airflow with filters installed and partially loaded. Balance supply and extract so the intended pressure differentials are maintained during production, not just at commissioning.

Housekeeping that supports classification

• Use cleanroom-rated, anti-static HEPA vacuums for floors and equipment. Avoid sweeping and dry brushing.
• Adopt top-to-bottom cleaning schedules with logged frequencies aligned to risk.
• Control consumables: low-shedding wipes, approved bags, and sealed waste stations near process exits.

Monitoring and maintenance

Trend airborne particulate counts and log alarms. Add simple spot checks with a handheld PM meter in support of formal monitoring. Inspect LEV and enclosures with smoke visualisation to confirm capture. Replace filters on condition, considering pressure drop and hours, and re-verify after change-out.

Practical takeaways

• Design pressure cascades around the process, not the floorplan.
• Prioritise source capture at weighing and post-processing.
• Confirm HEPA H14 performance and airflow under load.
• Standardise cleaning with HEPA vacuums; avoid re‑agitation.
• Trend particles and re-balance after any change to equipment or filters.

Keeping air quality stable is an operational discipline: small, consistent controls at process points prevent failures and protect yield.