Goggles/glasses are usually designated by the host of the game. Some hosts prefer the paintball goggles and will state specifically in their thread that paintball goggles are the only eye protection allowed. Nothing else. Mainly because they are "fully closed" and have no gaps that will allow a BB to pass through and cause damage. In the end, its your eyes. Protect them, you'll never get them back.
Just to throw it out there...the engaging range is 10 feet. I think that's what everyone plays with when they play the merci rule. It's just courtesy...if you want to light someone up at close range then ask yourself: "If this happened to me, would I get pissed off?" Do unto others as you would want done unto you. Chances are, if you engage someone up close and personal intentionally...that person will be back on the field in 5-10 minutes.
Gloves, face masks, any sort of 'armor' is not required or needed. But it's up to you. In door games (CQB) I would wear a face mask. I've been hit in the face at close range before, so a full face mask would be worn if I ever went into a CQB game. The BB's leave welts. They sting for like 10 seconds and then all you start thinkin' about is "Why did I leave myself open like that?" If you work in an environment where people will ask a lot of questions and they seem like they won't be completely open minded to your after hours hobby, cover yourself up as best as possible. Just to keep the bruising to a minimal and the questions to a minimal.
The Distance Between Courage & Stupidity Is Exactly Nine Millimeters