Required protection for copper gas line passing through metal opening in fireplace casing (Alberta, Canada)
For me, there is nothing wrong with the copper tubing used as long as it is not touching the sharp metal of the hole. For someone that is looking for anything to complain about, well it is time to correct the problem. You can "GOOGLE" CPVC bulkhead fittings or go to the web site  (PVC pipe supplies .com ) and click on the picture with the same heading for a possible solution. The fittings or similar item can be purchased at electrical stores or most home improvement stores that sell electrical conduit. A second fix may be to use a snap-in insulating bushing which you should be able to find at the same previously mentioned sources. A third fix would be to replace some of the copper with schedule 40 black iron pipe (standard piping ). You will of course have to disconnect the copper tubing to install the bushings.  Hope this helps.