Just wondering what depth I can safely drill into a concrete apartment ceiling without hitting wiring, pipes etc.. (Canadian apartment).
Building manager should be consulted, a guessing game is not productive and could be dangerous.
Call the city building inspectors and ask what the code would have been when the building was built.
Embedded items in concrete may or may not be located where pertinent codes say they should be. If the items are metallic, you can use a pachometer to readily spot their locations, and then drill any/all holes to miss those locations.