Convert Feet per Minute to L/(m²·s)

Formula

L/(m²·s) = ft/min × 5.08

Derivation from SI units:

• 1 ft/min = 0.3048 m ÷ 60 s = 0.00508 m/s
• 1 L/(m²·s) = 10⁻³ m³ ÷ (1 m² × 1 s) = 10⁻³ m/s = 1 mm/s
• 1 ft/min = 0.00508 m/s ÷ 0.001 m/s per L/(m²·s) = 5.08 L/(m²·s)

Both units are defined exactly, so the factor is exact. Foot per Minute definition: foot per minute; Liter per Square Meter per Second definition: liter per square meter per second.

Worked examples

1. A reading of 90 ft/min converts to 457.2 L/(m²·s).
   90 ft/min × 5.08 = 457.2 L/(m²·s)
2. A value of 300 ft/min is 1524 L/(m²·s).
   300 ft/min × 5.08 = 1524 L/(m²·s)

Where it's used

Feet per Minute are used for fume hood face velocity (commonly 80–120 fpm), while liters per square meter per second appear in fabric and nonwoven air permeability (EN ISO 9237 at 100 Pa or 200 Pa). Both measure face velocity and air permeability (volumetric flow per unit area), so the conversion is a fixed factor.

Foot per Minute to other face velocity & air permeability units

Frequently asked questions

Sources

• Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "foot per minute (ft/min)".
• ISO 9237:1995 Textiles — Determination of the permeability of fabrics to air, International Organization for Standardization , air permeability expressed per unit area.
• The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 8 (litre).

Last reviewed: 2026-10-15. Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.