Guanyu Zhou explained that one of the possible reasons for the broken St. Anthony's in the accident at the start of the British GP was the much stronger impact than predicted in the FIA safety tests

The halo was crucial to the survival of Guanyu Zhou after the strong accident at the start of the British GP, but the breakage of a particular piece lit the alert in the FIA (International Automobile Federation): The Santo Antonio, which occupies a space above the driver's head precisely to prevent the competitor from being exposed to the asphalt, did not resist the rollover of the Alfa Romeo car.
The entity has launched an investigation to find out what may have caused the breakdown of a fundamental item for the safety of drivers in cases of strong accidents, such as the one seen at Silverstone. And Zhou believes that one of the reasons was the violence of the impact.

Speaking to journalists in Austria, host of the 11th round of the 2022 season, the Chinese driver gave details of what he experienced during the accident and gave his opinion on the breaking of the St. Anthony. "The team is still investigating that first impact, when the St. Anthony broke, but I believe it was a much heavier impact than the ones already made in safety tests," he assessed.
George Russell's initial touch caused Zhou's C42 to roll over, and the St. Anthony was destroyed shortly after the car touched the ground upside down. The halo, however, withstood the impact and saved the #24's life.
"It was a much heavier impact than the actual numbers we want. So, certainly, that created the whole problem that immediately followed," added the Alfa Romeo representative.
A detail that draws attention is the concept of Alfa Romeo's protection piece, which would be in a "blade format", already adopted by Mercedes in 2010 and by Force India in 2011, but which fell into disuse mainly after the introduction of the halo in 2018. It is worth remembering, however, that the team's car, as well as all the others that make up the grid, passed the impact tests conducted by the FIA earlier this year.