Air Chamber on Basement Washer Lines

I am planning on replacing a section of galvanized pipe in a basement that is running to a spigot that feeds the washer. I have installed these chambers on above grade systems easily by installing a T and attaching the chamber to the top portion of the T but I'm not certain the proper way to install this since it's below grade and the water lines are currently following the rafters to a 90 deg elbow and then straight down about 3 ft. to another 90 that connects to the spigot. Should I install a T prior to the spigot and then elbow off to the side into an air chamber? or something else?

Hope that all makes sense!

I see couple of solutions;

1. Do nothing and if your washer valve has a problem with water hammer proceed to 2 or 3. I rarely see these on a W/D hookups and I think the hoses help absorb some of the pressure wave limiting the problem.

2. Tee and elbow off like you describe.

3. Buy an arrestor that uses a balloon that can be installed in any orientation.

I think Oatey has boxes with built in arrestors.

Edit: They do. Link Here

You can also add these to any washer