Tonight's fireworks got me wondering: With all of the firework displays happening at the same time, how do they keep aircraft away from them? Is there any risk of collision or blinding the pilots? Is there anything that pilots need to do differently when fireworks are in the area?
In canada and I assume in a similar way in the United States, fireworks are treated like any other obstacle such as a communication tower, building, or crane. The location and elevation of the firework activity is assessed for impacts to any instrument procedures, airways, minimum altitude areas, etc. and NOTAM to temporarily amend affected procedures will be issued prior to the activity to advertise the changes and their effective periods.
Having said that, this doesn't address the VFR side of things. Operating near fireworks is essentially the same see and be seen idea. NOTAM get issued here all the time for the fireworks activity themselves and they would include a radius from the centre point. Simply avoiding the area is usually sufficient.
In addition to the previous answer, there are often TFRs (Temporary Flight Restrictions) around the areas of organized fireworks displays- before you fly you're responsible for knowing where these locations are and not flying into that airspace.
As far as avoiding the stray bottle rocket, hopefully you're high enough in cruise and lucky enough in takeoff/landing to avoid these hazards.
As far as blinding, the fireworks can take away your night vision if you're close enough but I don't think it would blind. At least it has never happened to me.
Most firework displays peak at about 200 feet above the launching site. Any aircraft low enough to tangle with fireworks is too low anyway.
Pilots see fireworks as little flowers on the ground. They are not big or impressive from the air.
Also, the individual stars, and even the shells, do not weigh much. Unless a firework went into a jet engine, it could not damage an aircraft.