I just know I'm going to regret this, but.....
Simple, as I've already discussed the Adverse Weather Policy Shell introduced nearly 20 years ago, which is a risk based approach to controlling the hazard
An Adverse Weather Policy sounds simply like professional common sense. There is no need to wrap it up in some form of mystique and call it safety management.
And, by the way, a policy is not a safety case, nor is it a safety management system. It's a policy. This one, perhaps, crossing the line into an operational procedure. A safety case will present an argument for why the policy will assure an acceptable level of safety and evidence to show that the arguments are valid.
But, hey, what do I know? I don't work for Shell.