Symbology

Purpose

Standard symbols in mapping wildland fires facilitates fast and consistent interpretation of mapping products and helps prevent ambiguous map interpretation, which can become a safety issue during an incident. In the interest of encouraging safety, consistency, and readability, GeoOpS describes the symbols that everyone should use when creating maps.​

Specifications

The following applies:

  • Symbols should be identifiable and clearly distinguishable from other Incident Command System (ICS) symbols, whether displayed in color or black and white.
  • Common map conventions (e.g., blue for hydrologic features) should be observed, if possible, to ensure clear communication.
  • National symbology standards should be used where appropriate. See references below.
  • Choice of symbol size is at the discretion of the Geographic Information System Specialist (GISS) and the Situation Unit Leader (SITL)​.
  • Latitude/Longitude information is displayed in degrees, decimal minutes, WGS 84 datum.
  • Division and branch break locations, event point attribution, and labeling should follow the guidelines in the references section below.

2021 Updates

Point and Line symbols have undergone a redesign to give the entire dataset a more cohesive look and bring ArcGIS Pro and ArcGIS Online symbols into closer alignment. There is still not enough complexity supported in feature services to allow for a single cross-platform symbol set, but the new symbols are a step towards what is expected in 2022 to make a single set possible.

New symbols have been designed to coordinate with new grouping of Event Features based on use.

References

Divisions and branches divide an incident into geographical areas for the purpose of work assignments and delineating areas of operation. A Division Supervisor (DIVS) supervises the resources assigned to a division. A branch is the organizational level having functional or geographical responsibility for major parts of incident operations such as divisions. Divisions exist within specific branches. Operations Branch Director (OPBD) supervises DIVS on large incidents which contain branches.

Characteristics of Divisions

  • Divisions are identified by letters of the alphabet.
  • Usually start with “A” at the fire origin and progress in a clockwise order around the incident.
  • It’s common to skip some division letters to allow for expansion of the incident (e.g., Div A, Div B, Div Y, Div Z).
  • Division map label example: Div A, font 18-24 pt. and Bold (for 8.5x11 or 11x17 IAP map, scale accordingly for larger layouts/different maps).
  • Division labels are placed away from the fire edge, between the break symbols, and should not obstruct key features on the map.
  • As an incident winds down, adjacent divisions may merge into a single division or be combined (e.g., Div M/N/O), usually temporarily.
  • The symbols used at the break between adjacent divisions are point features and should be perpendicular (rotated if needed) to the fire perimeter.
  • Division breaks might not occur on the fire perimeter. These are commonly referred to as “floating” divisions. Division labels for divisions that are not on the fire perimeter are placed outside of the imaginary line between the division breaks.

Characteristics of Branches

  • Typically consist of 2 or more divisions.
  • Branches are identified by Roman numeral labels (or by functional name).
  • Functional branches oversee a specific function on the incident: Fire Suppression, Air Operations, Law Enforcement, HAZMAT, Structure Protections, etc.
  • Fire Suppression and Air Operations Branches are the most common found on wildland fire incidents.
  • Map label example: Branch IV, font 18-24 pt. and Bold (for 8.5x11 or 11x17 IAP map, scale accordingly for larger layouts/different maps)
  • Branch labels are placed a good distance away from the fire edge, between the branch breaks symbols, and should not obstruct key features on the map.
  • The symbols used at the break between adjacent branches are point features and should be perpendicular (rotated if needed) to the fire perimeter.
  • Branch break symbol may serve as both the break between branches and the break between adjacent divisions (i.e., replace a division break symbol).
  • Branch breaks might not occur on the fire perimeter. A branch may be assigned to an isolated area of an incident or another smaller incident within the main response area. These are commonly referred to as “floating” branches. Branch labels for branches that are not on the fire perimeter are placed outside of the imaginary line between the division breaks.

Event Point Attribution

While the Label Points feature class can be utilized for labeling divisions and branches, it is still necessary to populate the Label field in the Event Point feature class for reference (metadata). This is especially important on larger incidents with potentially dozens of divisions and several branches. Maintaining labels in the Event Point feature class helps identify those point features.

Labeling

Divisions and Branches must be labeled in between symbols. Labels should be in a clear area and not cover any incident or map features (roads, trails, etc.). To standardize how attributes are entered for divisions and branches, the Label attribute in the Event Point feature class should be populated with the division/branch (e.g., Div A or Branch I) that is clockwise (indicated with blue arrow in the graphic) of the break. Use the Comment field to indicate which divisions are broken (e.g., Div A/Z break) by the division or branch break. And when branches exist on the incident, also indicate in the Comment field which branch the division is in.

Map showing a fire perimeter on shaded relief with labeled Division and Branch breaks, highlighted with boxes and arrows to show location.

Table showing highlighted Label and Comment fields used for the map.

Division and Branch labels are often converted and stored as geodatabase annotation. Annotation provides a high level of control of the placement and content of layout text elements and are reusable in multiple layouts.

Responsibilities

The SITL ensures that standard map symbology is used for mapping wildland fire incidents. The GISS uses the standard GIS map symbology and, if applicable, standard map symbol colors but may adapt (e.g., enlarge, use halo) the symbology for map readability while maintaining the essential design of the standard symbols.

 

Page Last Modified / Reviewed: 
2021-07-20