There were two harrowing crashes on Sunday at the British GP.

At the start of the F1 showpiece, Zhou's Alfa Romeo was flipped upside down at 160mph at the first bend before skidding across the gravel and over the tyre barrier, into the catch fencing.

Earlier in F2 support race, Hauger's car landed on top of Nissany's.

• Sainz wins incredible British GP | Hamilton third, Max woe
• Zhou: 'Halo saved me' in upside-down crash | Albon also given all-clear
• Should Hamilton have won the British Grand Prix?

Incredibly, all drivers involved were uninjured, but both the incidents could have killed drivers without the halo, which sits on top of the cockpits and was first brought onto cars - to much criticism over aesthetics - in 2018.

"We sometimes criticise the FIA [F1's governing body] but you need to give it to them, how much they've been helping us," said Ferrari driver Sainz, the eventual British GP winner. "They've saved probably two lives.

"We need to give it to them, [for] the amazing work in safety."

Zhou's car ended up lodged on its side near spectators but he was conscious throughout the crash before he was stretchered to hospital, where he was given the all-clear. He returned to the paddock later on Sunday.

"When I saw it, I was completely shocked," explained Sainz. "It was incredible. The fact he came out of it... is crazy. I find it incredible that you can come out of it."

Zhou also posted on social media on Thursday that the halo 'saved me'.

The halo has been credited with saving many other lives, with Lewis Hamilton praising it after his crash with Max Verstappen at the 2021 Italian GP, and Charles Leclerc following the carnage at the start of the Belgian GP in 2018.

Perez: We shouldn't talk about driver salary cap now

Zhou was hit by George Russell, who in turn was nudged by Pierre Gasly, to prompt his scary crash on Sunday, while Hauger was forced off track by Nissany before launching into the air by a sausage kerb, back on top of him.

Nissany has been handed a five-place grid drop for the next race.

Sergio Perez finished second in the British GP and said he was "shocked" by the Zhou accident, which led to a lengthy red flag before the race restarted with another standing start.

"It's been a while since we saw such an accident like that," said the Mexican. "It's hard to see that and to try and delete it on your mind and focus on what you have to do.

"Well done to FIA because we've come a long way."

Perez also said it should end speculation over putting a cap on driver salaries.

"We are the ones putting all the risk out there, giving a show," said Perez. "So I don't think it's a good thing to be talking about that moving forwards. The most important thing today is no one got hurt."