LP tank gas plumbing bonding

What are the requirments for bonding either CSST or black iron gas lines from LP tank to appliances?

In my area, LP uses copper tubing which is run underground from the storage tank to the exterior wall where it connects to the PR, then into the home. I have never observed any grounding or bonding other than the copper tubing earth contact.

This CSST document says anywhere downstream of the secondary LP regulator
http://www.csstsafety.com/Images/CSST-Direct-Bonding-Tech-Bulletin.pdf

They have started to ground propane systems around here in most cases

NEC 250.104(B) Other Metallic Piping. If installed in, or attached to, a building or structure, a metal piping system(s), including gas piping, that is likely to become energized shall be bonded to the service equipment enclosure; the grounded conductor at the service; the grounding electrode conductor, if of sufficient size; or to one or more grounding electrodes used. The bonding conductor(s) or jumper(s) shall be sized in accordance with 250.122, using the rating of the circuit that is likely to energize the piping system(s). The equipment grounding conductor for the circuit that is likely to energize the piping shall be permitted to serve as the bonding means. The points of attachment of the bonding jumper(s) shall be accessible.

Informational Note No. 1: Bonding all piping and metal air ducts within the premises will provide additional safety .

Informational Note No. 2: Additional information for gas piping systems can be found in Section 7.13 of NFPA 54-2009, National Fuel Gas Code.

any site specific installation ?s should be directed to the ahj