var imageFiles_z_1 = new Array();
imageFiles_z_1['0'] = new Array ('_images/z_Air_Polution_Control_Equipment.gif', '_images/z_Air_Polution_Control_EquipmentMouseover.gif');
imageFiles_z_1['1'] = new Array ('_images/z_Energy_Enhancement.gif', '_images/z_Energy_EnhancementMouseover.gif');

function image_on_z_1 (position) {
   var doc = eval("document.imagez_1" + position);
   doc.src = imageFiles_z_1[position][1];
}

function image_off_z_1 (position) {
   var doc = eval("document.imagez_1" + position);
   doc.src = imageFiles_z_1[position][0];
}