Flexible copper tubing carrying propane at interior, OK?

In Colorado it’s common to see flexible copper tubing carrying propane outside the home, but unusual to see it inside. County Bldg. dept. says it’s OK if it’s listed. Well, it was 30 years old and had nothing written on it. It was out of the path of travel, so not likely to get bent/kinked. My feeling was… not great but not dangerous.

I didn’t call it, but told the clients I didn’t see it often inside homes, didn’t like it much and would check it out.

Anyone feel real strongly about this one way or the other?

Kenton I am like you don’t like copper with propane in the interior but it is allowed in Ok. don’t know about CO. My reason is that most folks don’t know how to put a good flare on copper they just think they do. Factory flares are a little better but flare nuts have a tendency to loosen over time especially if subjected to different temperature ranges. I like threads.