Multiple pile-ups on Madrid-Toledo motorway in Spain

As I'll be driving down lengthy stretches of Spanish motorways (mostly the AP-7 and A-7) myself next week, news of three multiple pile-ups on the A-42 Madrid-Toledo freeway yesterday is rather worrying (a brief report in English is here). The area was affected by heavy fog and about 100 cars were involved with 68 people injured, of whom 54 had to be taken to hospital. Eight were seriously injured