When I crack a bottle I open it far enough(much more than a hiss) to blow whatever is in the throat, out, only for less than a second. Wastes gas -saves regulators. Don't get or let anyone/thing get in front of it during this operation. As I said I don't know what the latest protocol is these days. Maybe ask your gas supplier. It's great that you have solved your problem.---Meltedmetal