There is no law or even a protocol to ask that kind of question in OK. I think they are basically asking a general question about safety, maybe they were suggested to do so or it is in their personal interest. With that said I think they should control their questions to falls, drownings, poisoning, vehicle safety issues, household chemicals etc. It seems I remember hearing of a law in florida about doctors being required to ask something about firearms but not sure what the details are though.