I still have to say that in any case CF couldn't be imposed in 82 (the year of Villeneuve's death) because it's aplication in F1 was only 1 year old! Besides that at the time only 1 or 2 componies in the world had the facilities to build them....and fabricating for 12 or 13 teams would be impossible! Besides that it was simply too expensive at the time....only a fraction of the teams had the financial capability to use it!
Even nowadays teams don't have to use CF they simply opt to use it! They're not forced to use it!
In any case the probably Villeneuve would have died probably the washer wouldn't be in place anyway and would snap of the belt! Though not trown from the car probably would bang his head against the cockpit rim!
The changes imposed after Donnellys crash didn't alter properly the crash worthyness of the monocoque it just reduced the risk of feet/leg injury on head on colisions! The biggest problem with donnelly was the cockpit explosion....and they didn't change anything in this aspect! The moncoques were considered safe enough.
Well yes the FIA does test all the changes and are continuosly trying new stuff....but one change might be good in one area might be very bad in another! Look at the HANS device...though very good for the neck and preventing wipelash it doesn't prevent "brain" decelaration....this just to show that there isn't a solution for everything! The best idea would be cancel all kinds of motorsports....only this way we'd remove all the risk!
Concerning the track regulations tracks do have regulations during race weekends but for race sessions each track more or less has their own regs....at the moment if I'm not mistaken to test there has to be a helicopter present and at least one fire fighting truck....the number of marshalls isn't a regulated thing. (at least that's what I remember)
Well just went to FIA and found this:
16. Private testing at motor racing circuits (see also 9.3)
The FIA points out that it is not within its responsibility to regulate
private testing, the organisation of which has to be defi ned by
a contractual relationship between the user and the owner of
the circuit.
The FIA wishes however to clearly defi ne recommendations
concerning safety during private testing.
For any private testing involving very high speeds and intended
for vehicles which are later to take part in FIA competitions, it
is recommended that a set of minimum safety measures be
established with the owner of the circuit or his representative :
1) a medical service in conformity with article 9.3 of the present
Appendix H
2) installation of fi re-fi ghting marshals’ posts along the circuit with
adequate means of communication ensuring correct cover over
the entire track.
3) suffi cient fast vehicles for fi re-fi ghting.
4) the various teams are strongly advised to establish a standard
contract, identical for each of them, with the circuits on which they
wish to carry out their private testing.
So as you can see private testing isn't regulated.....so no changes have been made!