Actually, 2-tones (tone out compatible) are still used from time to time on the old dispatch frequency of 460.575. These are supposed to be used every time a non-routine call (non medical) is dispatched for any one of the volunteer fire stations in the county. Depending on the dispatcher, you may not hear the tones when you should.
Tone paging in Fairfax will probably be completely stopped in the near future, as we're currently (slowly) working on integrating an alpha-numeric paging system with the Altaris CAD system to automatically send text pages to volunteers, duty officers, etc.