Can I find out when Destructible component is fractured?

I have blueprint with destructible mesh component and a collision box(some why nav mesh is not generated on destructible meshes). Character can perform area damage and destroy few destructibles, I need to turn off collision on collision box, so there will be a hole in the floor, but I dont know how to find out when destructible is fractured, is there a way to know it? Or is it possible to make destructible mesh navigatable?

Resolved. I use Radial damage with radius of impact, so now I know the exact moment of fracture.