Unlike other viruses such as SARS and influenza, Ebola cannot pass through the air; it's only transmitted through direct contact of bodily fluids. Airborne illnesses are passed through inhalation of tiny virus-laden particles floating in the air. What makes all the difference in determining how airborne a virus may be is the size of the droplet through which transmission occurs. Fine mist aerosols (like those that occur when you cough or sneeze) linger in the air and can travel through it fairly easily.
Thankfully, unlike the flu, Ebola does not cause symptoms of coughing or sneezing. Technically, Ebola victims can send large droplets of contaminated bodily fluids into the air if, for example, they vomit onto the floor and some droplets splatter upward. But large droplets can't travel far, nor do they persist in the air for very long, making this transmission method a near impossibility.
In 2012, scientists discovered that Ebola was transmitted from pigs to monkeys without direct contact, but so far, this study isn't really of concern to us. Pigs generate large infectious droplets better than any other animal, and these may have easily been passed to the monkeys during cage cleaning. Plus, people aren't pigs or monkeys. All studies done with humans have shown no support for transmission to occur without direct contact [source: Poon].