The Coroner in the M5 crash inquest has dismissed the possibility that smoke from firework display caused the accident.
Some firework smoke carried over motorway - some lower level smoke carried in a different direction.
HSE, British Pyrotechnics Association and highways legislation has been examined - none contain a warning about risk from firework smoke in foggy conditions.
Coroner Michael Rose says "I was left with the impression that fireworks organiser Geoffrey Counsell was a competent operator who had been putting on displays for 20 years".
An explosives expert tells an inquest he has been unable to find any literature warning of the dangers of smoke from fireworks to drivers.
Drivers have told an inquest of their horror at being involved in one of the worst British motorway pile-ups in living memory.
Witnesses have been describing the driving conditions at the inquest into the deaths of seven people who died after a pile-up on the M5.