Column A of my spreadsheet has a bunch of part numbers. I would like
to create a formula in Column B such that my parts are either labeled
"American" or "Metric".

Parts that are to be labeled "American", have one (or more than one)
strings within their part number:

PT<space<space
TF<space<space
<spaceNPTF
<spaceNPS
<spaceDOT<space
<spaceUNF
<spaceNPT
<spaceNFPA

If none of the above strings are within a part number, then the part
is to be labeled "Metric".

Can somebody please help me in creating the desired formula?

Thanks.
--
Tiziano