How do I operate this valve?

[rural_engineer]

I'm fairly sure that I'm looking at a Ford Meter Box ball valve. I'm a little concerned because the handle attachment looks a lot like some sort of lift up pressure release. And I don't want to start a big leak where the water line enters my house.

Have I identified this correctly? Am I safe giving it a quarter turn to shut off the water in my house?

 

[Terry]

It looks to be a 1/4 turn shutoff to me.