On 05/15/2016 10:44 AM, Virgil wrote:
replying to Steven L Umbach, Virgil wrote:
I use white for water and Yellow for Gas in some places this is code you
have to check your local Inspectors the yellow is thicker with a higher density

Thickness yes, not any different otherwise (barring the color, of
course). White PTFE is single thickness, yellow is double and pink is
triple.

I know of nowhere it is in any Code requirement and unless it's been
changed which I think it hasn't, the National Fuel Gas Code handbook
2.6.7(d) refers to using pipe dope suitable for use with gas and says:
"This requirements does not prohibit the use of teflon tape as a pipe
dope. [Further comments regarding workmanship elided for brevity]"

The requirement for the thicker tape (hence yellow as common identifier)
is the only one I'm aware of.

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