Notam question - En-route or Nav warning

[ahs]

It may be a silly question - but can anyone explain the difference between an en-route NOTAM and a Nav warning NOTAM.

I'm sure there must be difference, but it's not clear to me why some are one and some the other.

Thanks,
Alan.

[flowman]

Not really my bag but after consulting my learned colleagues it would seem that:
En-route NOTAMs concern the closure/opening/realignment of en-route facilities such as airways, airspace, danger areas etc.
Nav warnings are related to volcanic ash, radio-active material or toxic chemicals released into the atmosphere.
If you are REALLY interested in the answer it's in here somewhere: www.icao.int
:ok: