Convert Square millimetres per second to Square feet per hour
Convert Square millimetres per second (mm²/s) to Square feet per hour (ft²/h) instantly and accurately.
Conversion Formula
ft²/h = mm²/s × 0.0387500775
About Square millimetres per second
The square millimetre per second (mm²/s) equals 1 × 10⁻⁶ m²/s and is the standard unit in materials engineering and the laser-flash diffusivity method (ASTM E1461, ISO 22007-4). Metals span roughly 2-180 mm²/s; polymers 0.07-0.2 mm²/s; ceramics 0.3-10 mm²/s. Numerically identical to the kinematic viscosity unit (cSt) in SI context. 1 mm²/s = 1 × 10⁻⁶ m²/s.
About Square feet per hour
The square foot per hour (ft²/h) equals ≈2.581 × 10⁻⁵ m²/s and is the dominant unit in US engineering practice for thermal diffusivity of building materials and industrial insulation. ASHRAE handbooks, Perry's Chemical Engineers' Handbook, and NFPA fire-resistance tables all list diffusivity in ft²/h. Steel: ≈0.4-0.5 ft²/h; concrete: ≈0.023 ft²/h; mineral wool: ≈0.005 ft²/h. 1 ft²/h = 0.09290304/3600 m²/s.
Quick Reference Table
| Square millimetres per second (mm²/s) | Square feet per hour (ft²/h) |
|---|---|
| 1 mm²/s | 0.0387501 ft²/h |
| 2 mm²/s | 0.0775002 ft²/h |
| 5 mm²/s | 0.19375 ft²/h |
| 10 mm²/s | 0.387501 ft²/h |
| 25 mm²/s | 0.968752 ft²/h |
| 50 mm²/s | 1.9375 ft²/h |
| 100 mm²/s | 3.87501 ft²/h |