We should just forbid any communications on non-work related themes. All communication should be done in text form or using a speech synthesizer to avoid possibility of others made feel unwelcome by your voice - may be it's your accent (hispanic, southern american or Queen's English, or any other), creepy heavy breathing or unpleasant lisp.
We should also prohibit any personal contact, lest somebody gets offended by someone's appearance or manners. Everyone should work in a completely isolated personal space, leave and arrive at work separately.
This way we'll create completely unbiased, gender-, race- and culture- neutral environment, equally (un)welcoming for everyone.