re: Do you use sir and ma'am with older coworkers?

I don't do it in military-like fashion, as I don't think that is appreciated in most settings.

But I use it in thanking people of all ages I encounter and in similar pleasantries ("thank you sir" for a dude who holds the door etc.). It's a little "lighter" in significance but also isn't going to rustle feathers of anyone who might otherwise think it's age-based.