But, sorry, your whole post sounds like a dismissal of any ash related risk.
Kerosene
I am repeating my position from the original thread on Ash. You talk about the manufacturers but their position was anything over zero ash was not acceptable.
The press and media blew everything up to a hysterical level which is the usual media way and the unknowing public responded in an equally hysterical way with some equally "way over board claims in the forum". One was that ash had a mystical property which unlike any other air particles was invisible.
Patent it and stick it on the next Stealth Bomber
So some of us were trying to be realists and to bring some sense into the arguement.
The fact is that no one yet really knows at what density Ash will cause serious and immediate damage that could bring an aircraft down.
The new criteria are a sock it and see guess.
As for piloting I would avoid in known ash areas flying into any visible clouds or mist areas especially pollution coloured clouds if at all possible.
The good old see and avoid.
My guess is that if you cannot see it then it will not do immediate damage.
Long Term damage is for the Airline accountants to work out and not our problem.
I would avoid flying at night which isnt a major problem at this time of year.
I would stick with the new ash criteria until the authorities get more field experience where they may raise or lower those acceptable limits.
Flight is a risk and many other threats like bird strikes are accepted yet other threats do have repeated fatality records over the last 50 years in aviation.
To date Ash has never killed anyone unless your a smoker
But I am only a bottom of the pile corporate jet Captain so what do I know?
Pace