Falling is something which can cause damage to people.
The initial formula is discussed on RUE pg 316 under the climbing skill - 1d6 damage per 10ft. That is an average of 7 dmg per 20 ft.
Pg 355 discusses an optional rule which allows SDC damage to be suffered inside MDC armor. It uses a formula (at the start of 356) of 1 dmg per 20ft. It also suggests 1d4 damage per 20mph of a crash.