Don't use microwaved water! I know you said you didn't have a microwave there, so thank your lucky stars. Not only is microwaved food transformed into a toxic non-food, water is also made harmful to the human body! Good old-fashioned boiling should do the trick. Don't know your office situation, but have you considered buying a water carafe? It is a pitcher you plug into an outlet that boils water in about 2 minutes. Widely used in europe, not much in america.