The following Airport Impact Area maps show the noise contours for ONT and the affected land uses. These contours are established by modeling annual operations at the airport and adjusting the levels based on actual noise measurement data for that time period. Each 4th Quarter map is based on calendar year information for the respective year. The contours shown are measured in CNEL (Community Noise Equivalent Level) for the 65dB, 70dB and 75dB noise levels. These maps will be updated quarterly during the current year as they become available. (The maps on this page are best viewed in the 1024 x 768 screen resolution.) - 2Q07 PDF format   (requires Adobe Acrobat Reader to view) - 1Q07 PDF format   (requires Adobe Acrobat Reader to view) - 4Q06 PDF format  (583KB) (requires Adobe Acrobat Reader to view) - 4Q05 PDF format  (725KB) (requires Adobe Acrobat Reader to view) - 4Q04 PDF format  (611KB) (requires Adobe Acrobat Reader to view) - 4Q03 PDF format  (671KB) (requires Adobe Acrobat Reader to view) - 4Q02 PDF format  (629KB) (requires Adobe Acrobat Reader to view) - 4Q01 Med size - 271KB Full size - 848KB - 4Q00 Med size - 257KB Full size - 834KB - 4Q99 Med size - 242KB Full size - 808KB