Millimeter per Hour to Foot per Minute

Millimeter per hour measures extremely slow movements in millimeters over an hour. Used for minute geological and material changes.

1 mm/h = 0.001 m/h = 0.0000001 km/h = 0.000000278 m/s.

To m/s: ÷ 3,600,000. To cm/h: ÷ 10. To m/h: ÷ 1,000.

Cave formation rates (stalactite/stalagmite growth), extremely slow material creep, and long-term geological monitoring.

Stalactite growth: 0.1–1 mm/h in active caves. Human hair growth: ~0.015 mm/h. Fingernail growth: ~0.004 mm/h.

Using for anything except the slowest processes. Confusing with mm/min (60× faster).

1,000 mm/h = 1 m/h. Extremely specialized unit. Think geological time scales.

Foot per minute measures distance in feet traveled in one minute. Common in US industrial and HVAC applications.

1 ft/min = 0.00508 m/s = 0.01829 km/h = 0.3048 m/min.

To ft/s: ÷ 60. To m/s: × 0.00508. To mph: ÷ 88.

HVAC duct air velocity (600–2,000 fpm), conveyor belts (50–300 fpm), elevator speeds (200–1,500 fpm), and escalators (90–120 fpm).

Typical HVAC duct: 800–1,200 fpm. High-rise elevator: 1,000 fpm. Airport moving walkway: 140 fpm.

Confusing ft/min with ft/s — ft/min is 60× slower. Mixing fpm with mph.

60 ft/min = 1 ft/s. ~88 ft/min = 1 mph. Essential for HVAC calculations in the US.