The largest safety threat to the ISS are the micrometeorite and orbital debris (MMOD) fires, impacts and toxic spills. These pose the biggest threat to the ISS astronauts.
Explanation:
The debris is as a result of collisions. An observation revealed that once a certain mass is passed, collisions give rise to more debris.
Another report revealed that the station has about 55% chance of being hit by tiny space rocks over a 10-year period. They can protected by installing new impact-protecting panels to the exterior of the station.
