What is Gridded floor plan / x-y grid overlay?

A gridded floor plan is a facility map or floor plan with a labeled coordinate grid (for example A1, B2) laid over it so responders can name and communicate precise locations during an emergency.

The grid gives police, fire, and EMS a shared reference for articulating where something is happening inside or around a building. Several state critical incident mapping laws specify this directly, requiring mapping data to include a gridded coordinate overlay layered on accurate floor plans and current aerial imagery. The grid is intended to be compatible with the software platforms responders use and verified for accuracy.

Defined from authoritative sources

This definition is drawn from the sources below, last verified 2026-06-23. How we verify.

1. New Jersey Revised Statutes 18A:41-7.1, Schools to provide critical incident mapping data to local law enforcement verified 2026-06-23
2. StateScoop: Critical incident mapping laws across states verified 2026-06-23

Keep reading

• Critical incident mappingDefinition
• Responder-ready mapDefinition
• True-north orientation (in emergency mapping)Definition
• Site plan / floor plan standard for first respondersDefinition

From definition to deployment

See how responder-ready mapping works for K-12 schools, where your state stands, and the grants that can fund it.