1. For Fire Pole and Plastic Ladder the word "Runspeed" and related tooltip does not make sense.
Duplicant does not walk -75% faster on Fire Pole. Also, Fire Pole is not a tile.
2. Some tiles have Runspeed effect with negative value but the tooltip still states that Duplcant can walk "faster" on them.
Open "Base Build Menu", click on Fire Pole or Transit Tube Crossing.