Poor lighting takes away visual cues and body language that many people need, especially people who may be hard of hearing. Any visual displays cannot be seen well in poor lighting conditions taking even more away from the communications process. Noise is another environmental factor that adversely effects communication. The noise can be traffic noise outside an office or place of business which blends into what is called white noise, or the noise of an annoying co-worker talking on their cell phone to a family member. Noise is simply anything that can be heard that is distracting and takes attention away from the intended communications.
Long distance can detract from effective communications in that it takes longer for verbal communication to reach its target and sometimes visual cues and body language are taken out of the equation. Technology has improved phone service to the public over the past few decades where communication via voice is now reliable to anywhere in the world, but without visual clues and body language the communication process is not at an optimum.
Visual noise can refer to anything that is distracting in a visual manner such as traffic going by outside an office window or a fight between co-workers. Once a person becomes interested in something other than the person talking to them, the communication process stops.
The key to effective communications is to recognize and eliminate all or as much of these environmental factors that take away from the communications process. While there may be some factors that you cannot control, the fact is there are many of them you can and should eliminate.