As of right now, based on the data available, staying away from the spill site is the best option (how much outside of the range is really dependent on the level of concentrations detected near the spill site and wind direction). If you are near the spill site, make sure that the air around your house is monitored frequently (recommended continuous monitoring). If you are well outside of the spill site, there isn't much concern as long as you don't get near any down gradient surface water bodies.