Air around CNC cells can carry fine dust, coolant mist and smoke, which drift beyond enclosures and into operator areas. Monitoring turns this invisible risk into actionable data that supports safer, more productive shifts.

Decide what to measure and why

Prioritise PM10, PM2.5 and PM1 to understand coarse, fine and respirable fractions. If materials generate respirable crystalline silica, align targets with HSE guidance (UK WEL for RCS is 0.1 mg/m³). Track trends rather than single spikes so you can link rises to tool wear, door openings or specific programs.

Place monitors where decisions are made

Position sensors at operator breathing height (about 1.4–1.6 m), near cell doors, along walkways, and at air returns. Avoid mounting directly in supply jets or dead corners. Use at least one sensor per cluster of cells and one in the shared corridor to see drift.

Build a baseline, then set alerts

Log a full week to capture shift, material and weather variation. Record machine states alongside readings. Once the baseline is stable, set alert thresholds a little above normal running so teams act early—clean filters, adjust LEV hoods, slow a cut, or schedule maintenance.

Combine fixed and portable checks

Fixed air monitors provide continuous visibility; verify them monthly with a portable particulate monitor and update placements after layout changes. Wipe optical inlets, replace filters as instructed, and keep calibration certificates accessible for audits.

Turn data into control

Use trends to tighten the three-layer framework: improve capture at source (tool extraction, enclosure integrity), control in the air (right-sized air scrubbers and negative air), and keep surfaces clean (H-Class vacuums, no sweeping). Where appropriate, tune LEV and air scrubbers, including MAXVAC units, based on measured under-load performance—not free-air figures.

Where relevant, integrate fixed air monitors with maintenance tickets so alerts trigger checks on seals, filters and coolant condition.

Practical takeaways

• Map 4–6 monitor points per line: operator, door, walkway, return air.
• Log one week to set your baseline; create shift-specific alerts.
• Correlate peaks to events (tool change, door open, program) to target fixes.
• Verify monthly with a handheld PM meter and re-site sensors after moves.
• Use alerts to trigger actions across source capture, air control and housekeeping.