Production flexibility contract pH -- An expression of the intensity of the basic or acidic condition of a liquid or of soil; may range from 0 to 14, where 0 is the most acid, 7 is neutral, and above 7 is alkaline on a logarithmic scale Natural waters usually have a pH between 6 5 and 8 5
Passenger Facility Charge, authority for a commercial service airport to charge each enplaning passenger a facility charge which can be used to preserve or enhance safety, security, capacity, and to reduce noise or to enhance competition among carriers