A foam mount of an aircraft window has a groove to receive an electro chromic window. The foam mount is painted by placing a blank in the groove to divide the foam mount into a first section designated to face the exterior of the aircraft and an opposite second section. The groove and the first section are coated with an electric conductive paint, and the second section is covered with a decorative paint. The conductive coating on the foam mount and the conductive coating of the electrodes of the electro chromic window provide an RF shielding to prevent electronic signals from personal electronic equipment from passing through the cabin and door windows of the aircraft. A mask is also provided to coat one section of the foam mount while covering the other section.