Currently , EMS units and Cops transporting to hospitals and jails , clear the hospital/jail immediately upon arrival.
Obviously,anyone who has transported to either place knows that your unit is stuck there for a certain amount of time , depending on how busy it is determined how long the wait it.
My suggestion would be a setting in the "transport settings " menu to allow a player to enable some type of hospital/prison arrival delay setting before the unit can clear. Perhaps a option of 15,30,45,60 minute delay before a unit can be clear of the building.