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I am replacing these two switches and not positive how the right switch is wired. The left switch is the only switch that runs to our porch light and the right switch is the only switch that run to the interior room light. It looks like it is a three way switch, but I am not sure since each of those switches operate as single pole switches.
Second question, even though the switch is grounded to the box, how can I tell if the box is actually grounded?
It looks like it is a three way switch, but I am not sure
It isn't. What I see is
That seems fairly straightforward to me
So, I don't see a three-way arrangement (two switches controlling one light)
Whether the use of colours is compliant with local code (regulations) depends on where this is located and when it was installed.
Sorry for the horrible diagram, I must find a better tool than MS-Windows-Paint!
As bib pointed out in a comment, my diagram omits one black wire from the left switch to the bottom left (room light) cable. I conjecture that this may have been to provide power to something like a ceiling fan with a separate pull-switch built into the hub - but that's just a guess on my part.
how can I tell if the box is actually grounded?
It probably isn't, unless there is a connection to the back-box we can't see (perhaps to the outer metal sheath of an amoured cable.
You can test this with a multimeter and, with all power to the building turned off and verified off, measure resistance between metal-back box and the white wires. If the resistance is low there is a ground connection between back-box and the neutral-ground bond near the main incomer or main panel.
I see two black wires and one red wire connected to each switch. If, for each switch, the two black wires are connected together, you have a bog standard pair of single pole switched circuits, with unswitched power also continuing on toward one of the loads.
The two black wires at each switch may be connected together by being clamped into the same terminal block, or into separate terminal blocks that are connected together inside the switch. That's why I want to know where you are, and I want to see a better view of the back of the switches.
Thanks for the help. The extra wire was from an old fan/light fixture, which is no longer there. That is where my confusion came from.
Assuming you are in the US, a quick way to tell if a switch is a three-way is that it will not have the words "off" or "on" on it; threeway switches can be mounted in either direction.
