Choosing the right HEPA grade is critical to controlling fine and respirable dusts on site. HEPA classes H10 to H14 are defined by EN 1822/ISO 29463 and relate to tested efficiency at the most penetrating particle size. In practice, higher grades capture more of the toughest-to-filter particles.

What H10–H14 actually mean

H10–H12 are lower HEPA grades typically used where the risk is moderate. H13 and H14 are high-efficiency grades used for fine, hazardous, or critical applications. For respirable crystalline silica (RCS) and other carcinogenic or very fine dusts, H14 filtration is generally required. ULPA filters exist above H14 but are rarely necessary for construction.

Picking the right grade for the job

• General nuisance and wood dust in air scrubbers: H13 is often suitable when combined with good source control.
• RCS, welding fume, or other fine/carcinogenic dusts: select H14 filtration. For asbestos, follow specialist regulations and licensed procedures.
• Industrial vacuums: match the machine class (M-Class/H-Class) with appropriate HEPA grade and seals.

System performance, not just the filter

Efficiency claims mean little if air bypasses the media. Look for gasketed frames, rigid housings, and verified sealing. Use prefilters to capture larger debris and extend HEPA life. Monitor differential pressure so you can change filters before airflow collapses.

Maintenance and assurance

• Change filters when pressure rises, airflow falls, or breakthrough is suspected.
• In sensitive environments, consider PAO/DOP integrity testing and keep records for COSHH.
• Always quote and check airflow under load; filter loading will reduce performance over time.

Practical takeaways

• Use H14 for fine or carcinogenic dusts such as RCS; H13 can suit general control.
• The seal matters as much as the media—eliminate bypass.
• Fit staged prefilters and watch differential pressure.
• Confirm control with a particulate monitor, not assumptions.

HEPA choice should fit into a three-layer approach: capture dust at source, scrub the air to manage what escapes, and remove settled dust with H-Class vacuums to prevent re‑suspension.