Ask pete that question i can't answer it, been asked on 50% of marine jobs for insurance certificate including marines work cover, rest of the time not, if they desperate I could see them not be too bothered but if there was a subsequent problem, and there insurers are paying out, Theni can see a whole torrent of poo heading over the hill, at this point I'd want to be insured.
As for blood out of a stone, its like this for me.
We are a limited company but that would count for Diddley squat as not having the cover in place would be a abandonment of my directorial duties and then I would be personally liable for the claim against the company, so not only would I lose my livelihood I would also lose my house/car/etc
If your a sole trader then its much simpler, your liable and they will have everything off you.
God this is a long thread,
moral of it is make sure your insured, True story three months a friends sister feel down stairs at work for a big plc, stairs cleaned that day and not dry and cleaner had taken home yellow slip signs, she's ok after a month off but company is claiming her salary plus lost productivity on the project she works on. its about £20k, his insurers quibbling as he had taken away signs so they think he's liable as it gross negligence,
Its not a massive amount but it would take most every business I know under at them moment, I'm cautious but thats just me, by all means fly close to the wind. But this is a litigious time.