New Delhi: In the wake of the Sunday collision between two trains in Andhra Pradesh that killed at least 14 people, the Railway Board has issued directions to all zones to conduct an intensive two-week safety dive from October 31. “Recent cases of SPADs (signal passed at danger) and accidents call for a resolve to strengthen alertness and enforcement of laid down practices and protocols in train operations,” the board said in a letter sent to the general managers of all railway zones on October 30.