Unless I read it wrong, OP fired the whole company/crew, not individual workers.
The company is responsible for workers that are improperly trained or out of control. If the supervisor can't enforce workplace safety rules, then the supervisor isn't doing his job, and if the company does not have process in place ensuring the supervisor is doing his job, then the company needs to be fined, too.
I can't believe we have this attitude of throwing up our hands and saying "Aww shucks, ya just can't convince those darn individual machismo men to do their job right. What can ya do?"
OP wrote "One of the crew still didn’t listen. I fired him." He fired the offending worker, not the whole company. Though in general I agree regarding supervisors.
The company is responsible for workers that are improperly trained or out of control. If the supervisor can't enforce workplace safety rules, then the supervisor isn't doing his job, and if the company does not have process in place ensuring the supervisor is doing his job, then the company needs to be fined, too.
I can't believe we have this attitude of throwing up our hands and saying "Aww shucks, ya just can't convince those darn individual machismo men to do their job right. What can ya do?"