If you do get roosted frequently, I recommend you get our Roost Protector. This is a wire mesh that sits above the scavenge fan, so any large pebbles won't hit the fan blades. The only downside to using this is that you need to do a pre-race inspection before each race to make sure no debris has built up on this screen as this would decrease the CFM of the scavenge exhaust which would reduce the efficiency of the Particle Separator itself.

The beauty of the Particle Separator is that it doesn't require maintenance, so unless you are getting roosted frequently, I would recommend not getting the Roost Protector and perhaps just have an extra Scavenge Fan on hand in the event the blades do get broken.