Safety criteria for the vital processor interlocking at Hoorn–Kersenboogerd

We formulate several classes of safety criteria for railway yards in terms of observable behaviour. These criteria are meant to protect trains from collisions and from derailments. We identify a number of safety criteria, and present instances of these classes for the case of the railway yard at station Hoorn–Kersenboogerd. These criteria have all been checked by means of the St̊almarck theorem prover, using a methodology from Groote, Koorn and Van Vlijmen.