Here are some excerpts from HaRav Neiman, that may be useful to readers of this thread:
It is forbidden to make small talk about matters unrelated to business. Men and women working together should not discuss politics, current events, recent tragedies or gossip, even if they do not do so regularly. Discussing these matters on a daily basis, is a violation of halachos that border on giluy arayos, which requires one to sacrifice his life rather than transgress. (p. 9)
When conversing with female employees or co-workers, one must be careful not to us the word “we,” so that the man and woman are not referred to as one unit. For example, one should not say, “We must talk with the editor,” or “We must purchase that software program.” Rather, he should say, “The editor must be consulted,” or “Please purchase that program.” (pp. 10-11)
It is a custom amongst yirei shomayim not to call a woman other than one’s wife or immediate family member by her first name, thus keeping a respectful distance between the two parties. Referring to a woman by her first name brings inappropriate familiarity into the relationship. Similarly, a woman should refrain from addressing a man other than her husband or immediate family member by his first name. (p. 20)
A Helpful Suggestion:
It is appropriate for male and female employees [to] refrain from all conversation when they meet anywhere outside of the office. This includes not discussing even job-related matters when meeting in the hallway or elevator at work.
“It cannot be stressed enough that the term prutzim also refers to people who are otherwise shomrei Torah u’mitzvos, but are not careful in matters relating to kraivah l’arayos. They may be regularly exposed to immodesty through the media, or may often be in the presence of immoral individuals through their everyday social interactions….(p.39) meaning that they are exposed to immodesty through television, movies, in publications and the like. An individual involved in such activities is labeled a parutz. This is not limited to visual images; someone who is exposed to any form of indecent activity, such as chat rooms on the Internet, is considered a parutz. Such forms of recreation are a breach of morality.” (p. 34)