Yellow tape round incoming gas main

[echoes]

Hello,

My street is having its gas main upgraded at the moment. This morning, a nice man had a look at where the steel gas main comes into the garage where the meter is, said it was fine, and then wrapped some yellow tape around a section of the pipe.
Can anybody tell me what this yellow tape is for? Many thanks.

 

[sooey]

It's just to identify the pipe as carrying gas.

 

[echoes]

Ah - it's that simple. Thanks!