Turning it 90 degrees clockwise (right) should turn it off.

I meant to say right to turn off, my mistake. So you think its a quarter turn and not one that I would continue to turn past 90 till it seats to turn it off?

Quarter turn.

It likely will just continue turning, and at 180 degrees will be open again.

The passage is a hole drilled though the piece you are turning.
Aligned with the pipe gas passes through, 90 degrees and no gas passes through.

If you look carefully at the top of the square there should be some marking that indicates open and closed.

Thanks for the replies.

Unfortunetly there are no markings that acutally say "open" or "closed" however, if you look at the photo at the link above. The square portion of the valve (the shutoff) is in the on position in a diamond like position. In the center of the "diamond" there is a circle with 2 arrows on top and bottom one pointing up and down.

This is in the on position I assume if I turn the arrows to point left and right it will be inthe off position. Unless they are just insignificant markings on the valve, do you think these indicate "open and closed"?

I hope my questioning is not silly I just never seen a valve with a shutoff that didnt have a handle...

"The square portion of the valve (the shutoff) is in the on position in a diamond like position. In the center of the "diamond" there is a circle with 2 arrows on top and bottom one pointing up and down. "

That is all the marking they often have.

Sometimes it is just a casting line.

SO Brickeye.. this casting mark, if the arrows are in the side position (square still in diamond position) then the valve is closed..... generally speaking of course.

If te line on the valve is across the pipe flow is blocked.

If it is parallel to the pipe flow is open.
Just like the handle on a ball valve.

Parallel is on, perpendicular is off.

You need to be aware these are maintenance valves, and not designed for a lot of use.

using them more than once every few years is liable to result in leaks.

The valve 'packing' is often just finely ground mating surfaces in the valve.

Would this be a valve shut off?

?