In the complex world of air purification, navigating international standards is the first step toward a high-performance system. The most widely recognized benchmark for filter efficiency remains the EN779:2012 (and the transitioning ISO 16890), which categorizes filters into Primary (G1-G4), Medium (M5-M6), and Fine (F7-F9) grades.
G1-G4 (Primary Filtration): These are your “first responders.” Designed to capture large particles (>5μm) like sand, lint, and hair. As a source factory, we recommend G4 pre-filters for almost all industrial HVAC systems to extend the life of more expensive downstream filters.
F5-F9 (Fine Filtration): This is where precision begins. F5 grade (often called EU5 in Europe) is the “gold standard” for ceiling filters in automotive spray booths.
Why it matters: Using a G4 filter where an F5 is required will result in “paint pimples” and surface defects. Conversely, using an F9 filter without proper pre-filtration will lead to rapid clogging and wasted energy costs. Understanding these grades allows you to balance air purity with operational economy.
