Methodology
The primary signal is enc 0/1/2. The mode field corroborates encryption when it uses DE; uppercase indicates full-time and lowercase indicates part-time.
Grade score formula: ((fullyEncrypted + 0.5*partial)/total)*100.
Control, data, paging, LCN, link, and other non-voice rows are stored but excluded from the denominator.
Agencies and trunked systems
Most modern public-safety encryption lives on trunked radio systems (their talkgroups), not on conventional agency frequencies. So county and state grades combine two kinds of public-safety radio source: the agencies in an area (scored from their conventional voice frequencies) and the trunked systems that serve it (scored from their voice talkgroups). Each agency and each serving system counts once per area. This per-area figure is source-weighted.
The national headline is weighted differently: it is the share of all individual public-safety voice channels (conventional frequencies plus trunked talkgroups) that are encrypted, with partial counted at half weight. Because a single statewide system carries thousands of channels, this channel-weighted figure is the most defensible single number — and it differs from a simple count of agencies.
The two metrics are intentionally distinct. The source-weighted per-area percentages will not average up to the channel-weighted national headline, and they are not meant to — a state of many small clear agencies and one large encrypted statewide system reads very differently per source than per channel. Both are published, each labeled with its weighting, in the open dataset.
Public safety metric
The topline metric and grades are public-safety-only. Public safety categories are law enforcement, fire, EMS, and public safety other.
Government, utility, transportation, aviation, business, venues, schools, hospitals, media, amateur, military, and federal rows are browsable but excluded from the headline.
Context-aware grade
Grades are computed for the specific geography being viewed, in the transparency direction — more encryption earns a worse grade.
A+ = 0%, A ≤ 5%, B ≤ 20%, C ≤ 40%, D ≤ 65%, D- ≤ 80%, F > 80%.
FAQ
What does encrypted mean here?
Encrypted means public-safety voice traffic is not monitorable from the published channel data. Partial means only some scored resources are encrypted.
Where does the data come from?
The site uses derived status and aggregate classification from RadioReference source records, with per-record links back to the source for verification.
How is the score calculated?
The grade score is ((fullyEncrypted + 0.5*partial)/total)*100 after excluding control, data, paging, link, LCN, and other non-voice rows.
Do you count trunked systems, not just agencies?
Yes. Most modern public-safety encryption lives on trunked radio systems (talkgroups), not conventional agency frequencies. County and state grades combine both the agencies in an area and the trunked systems serving it. The national headline is weighted by individual public-safety voice channels (conventional + trunked), which is why it differs from a simple count of agencies.