We had a plumber install a natural gas line to an outdoor kitchen and now I need to finish up and hook up the grill and burner. When I opened the shut off valve some liquid shot out before the gas (is this normal?) Also, he did not install a sediment or drip line, do I need to install one (in arkansas) for this liquid? Also the grill and side burner are different manufacturers. The burner came with a natural gas regulator, but the grill did not. DO I need this regulator? I am thinking the gas line into the house must already have a regulator.

Thank you very much for the help

it is not normal to have liquid come out of your gas line.
if you can install a drip leg then it will not hurt to have one.
there are unique regulations to follow if you grill is movable.
if it is fixed/stationary just pipe it like a regular stove.
the cooktop should not need a regulator for natural gas. it will need the orfice for the burner/s to be the correct one for natural gas.

An "appliance regulator" evens out the fluctuations in the main line regulator, and delivers the design pressure, which may be lower than the utilities pressure.

any gas cooktop I have installed came with a regulator. didn't matter NG or LP. if the manufacturer wanted a regulator, they would have sent one.

Doesn’t the regulator question go to whether that outside branch is running at 2 psi vs 1/4 psi? (7” wc)

YOu have never heard of parts being discarded because someone though they were useless or redundant?

"YOu have never heard of parts being discarded because someone though they were useless or redundant?"
I do it all the time.

Same way with the instructions? Insructions? INSTRUCTIONS? We don't need any stinkin' instructions!