911 is a location, not a prefix · Worked example

Quote the right page

Write the dialing rule, the partner, and the geography gap.

No prefix
RedSky
Which document says Canada

You did not merge the two maps.

Prefix? None. Dial 911.
Partner on the sheet? RedSky.
Wrong address? The EULA says the call can fail.
Same map on both docs? No. Cite which one.

Sources and go deeper

E911 data sheet. vendor. last checked 2026-10.
End user license agreement. vendor. last checked 2026-10.
Enhanced 9-1-1. wikipedia. last checked 2026-10.
confirm. The 2022 data sheet says US and territories. The EULA text this lab read also says US or Canada. Re-read both before you publish a coverage map. last checked 2026-10.