  Automated driving systems are subject to various kinds of uncertainty during
design, development, and operation. These kinds of uncertainty lead to an
inherent risk of the technology that can be mitigated, but never fully
eliminated. Situations involving obscured traffic participants have become
popular examples in the field to illustrate a subset of these uncertainties
that developers must deal with during system design and implementation. In this
paper, we describe necessary assumptions for a speed choice in a situation in
which an ego-vehicle passes parked vehicles that generate occluded areas where
a human intending to cross the road could be obscured. We develop a calculation
formula for a dynamic speed limit that mitigates the collision risk in this
situation, and investigate the resulting speed profiles in simulation based on
example assumptions. This paper has two main results: First, we show that even
without worst-case assumptions, dramatically reduced speeds would be driven to
avoid collisions. Second, we highlight that design decisions regarding
occlusion treatment are directly related to the risk that automated vehicles
pose to pedestrians in urban environments. In this respect, we conclude that
there needs to be a broader discussion about acceptable assumptions.
