NENA i3 data model v3 adds site-structure polygons and tighter validations, presenters say

Subject-matter experts on the Public Utilities Commission’s PUC 911 GIS series described planned changes in the NENA i3/data model version 3 and urged jurisdictions to treat conditional legacy fields as operationally important during the NG9‑1‑1 transition.

Sandy Stroud, public safety director at OneSpatial, said there is “not a straightforward answer” about which legacy attributes will ultimately be required because the data model draft is still being finalized. She and other panelists emphasized jurisdictions should understand why conditional elements exist because core service providers often need them to produce a geospatially derived MSAG and to validate data during transition.

Panelists said data model v3 aligns with I3 v3 and includes several notable changes: the addition of county fields; redefinition of elevation/altitude/height attributes; updated domain values and stricter validation rules; and a new site-structure polygon type in addition to site-structure address points. Carrie Brennan, subject-matter expert at GeoComm, said the site-structure polygon is “the first step to an indoor mapping data structure” and that an indoor data model working group is building further requirements.

Panelists explained why the site-structure polygon matters operationally. Stroud said site-structure polygons could be derived from CLDXF-compliant indoor maps and then used in Location Delivery Format (LDF) validation to support sub-address (unit/room) resolution in dispatch systems. Those polygon/address relationships can be costly to create, she cautioned, but may future‑proof indoor‑mapping investments because polygons can support both tactical mapping and core‑service validation.

The panel also tied the data-model changes to the FCC’s push toward end‑to‑end spatial call routing. Brennan and others noted the FCC report-and-order process is encouraging jurisdictions to have the full set of GIS layers ready for spatial routing: there is an implementation window once a jurisdiction requests transition from the FCC, with core service providers expected to begin delivery and a second phase potentially following within months.

Presenters recommended jurisdictions prepare now by understanding the purpose of conditional fields, building relationships between site-structure address points and sub-address records where possible, and planning workflows for ongoing maintenance. Becky Nordine, AGI solutions engineer at GeoComm, closed by urging agencies to “never underestimate the importance of developing a good workflow” for updates and maintenance.

Panelists pointed attendees to upcoming standards forums and NENA/standards workgroups for technical details and encouraged agencies to engage early with vendors and core‑service providers when scoping indoor mapping and LDF validation work.