Loudish fans in offices aren't always terrible. Computer noise is generally pretty continuous, so you hear less noise from the sound (sound is pressure fluctuations around P0, noise is what you hear). Speech OTOH has a lot of amplitude modulation, so is harder to tune out & more distracting - to solve this, it's common for offices to inject white noise (or some other colour) to cover office conversations. Computer fan noise is also a nice steady broadband hum, so fulfils a similar function.
Sound is easy to measure and quantify, noise depends on who's hearing it and what else is around.