Filter media gram weight explained

What gsm measures. Grams of media per square meter of filter face area. Standardized comparison metric across media types, easier to compare a 300 gsm polyester to a 350 gsm fiberglass than to compare proprietary product names.

Higher gsm tradeoffs. More material per area = more overspray-holding capacity (longer cycle), higher capture efficiency (catches more fine particulate), higher pressure drop (more airflow restriction). Higher cost per kit due to more material.

Lower gsm tradeoffs. Less material per area = lower holding capacity (shorter cycle), lower capture efficiency, lower pressure drop. Lower cost per kit.

By filter position. - Intake-ceiling diffusion: typically 100-200 g/m². The intake side optimizes for diffusion uniformity over capture density. - Exhaust pad: typically 250-450 g/m². Higher density to handle overspray load. - AMU pre-filter (panel): rated by MERV rather than gsm typically; the underlying media is in the 50-150 g/m² range. - Andreae / accordion paper: rated by paper basis weight, geometry-dependent capacity.

Booth manufacturer spec. Each booth has a specified pressure-drop tolerance for each filter position. Substituting higher gsm than spec restricts airflow more than the booth was designed to tolerate; the AMU and exhaust fan may not deliver design volume against the higher pressure drop. Lower gsm than spec under-protects.

Per-cycle cost math. Higher gsm typically wins per-cycle in higher-volume shops (longer cycle outweighs higher per-kit cost). Lower gsm wins per-cycle in lower-volume shops where the cycle-length advantage doesn't compound enough.