If you are in a performance class B aeroplane (small props mainly), there may be a height below which an engine failure requires you to land straight ahead even if there is insufficient runway. Typically this is the point where the u/c has fully retracted. If this is the case then for planning purposes you must assume an engine failure at that point, and your RVR for takeoff is limited according to the table you are referring to. In class A aeroplanes (all jets and turboprops >5700kg) you assume the engine fails at V1 on the runway and there is a separate table of RVR against runway markings/lights since it's all about keeping straight on the ground before liftoff.
Hope this helps.