Crew is suppose to protect both life and station alike, so blowing up the station to stop the station from blowing up is not very productive nor fun.
Minor explosions
Use of minor explosives (IED’s, modular grenades, potassium bomb etc) against imminent station threats such as nukies is generally fine as the damage is not major that often. Limitations on this is for example suicide bombing with a backpack full of explosives before the bomb is armed, your character still wants to live and the situation is imminent but not that dire. Rule of thumb is that the damage should be repairable with minimum effort.
Major explosions
Use of maxcap and other highly destructive grenades and explosives is generally never allowed to be used against station threats, at that point you are doing their job for them.