Jul.8 (GMM) Charlie Whiting, the FIA's top F1 official, has described Maria de Villota's crash earlier this week as a "one in five million" freak accident.
"It was so incredibly unfortunate," the race director, starter and technical and safety delegate told the Spanish sports newspaper Marca at Silverstone.
There have been suggestions Marussia was at fault for putting an inexperienced driver - who does not have an FIA super license - at the wheel of a powerful 2012 single seater.
And the fact a truck was parked nearby with its tail-lift positioned at visor-height has also raised questions about negligence.
"I think that if Felipe (Massa)'s accident (in 2009) was one in a million, then Maria's was one in five million," Briton Whiting added.
"The circumstances were just so unique that it was just incredible bad luck," he said.
Whiting said that, even at the time of de Villota's incident, the FIA was already looking at ways to better protect the drivers' heads.
"With the kind of protection we are studying, an accident like that would be unlikely, but also the chances of repeating these same circumstances are so remote," he said.
"We're looking more at the case of an impact with a wheel, because this can happen several times in a year. Maria's circumstances may never occur again," added Whiting.
Referring again to the head protection studies, he continued: "We can only do it as fast as we can, because it's a very complicated matter.
"In Maria's case, yes it (head protection) would have worked, but perhaps in many other cases the problems would be worse, like extraction or visibility.
"We have to make sure we aren't making something better for one type of accident but worse for three more."
The German newspaper Kolner Express said members of the Marussia team have been banned from talking about the de Villota incident this weekend at Silverstone.
Peter Sauber is quoted as saying: "I know as much as you do -- or even less."