The Emergency Response Guide (ERG) web tool enables users to visualize and analyze hazardous material spills directly within ArcGIS Online and ArcGIS Enterprise. The tool supports emergency planning and response by following distance guidance from the 2024 Emergency Response Guidebook’s orange and green pages, including:
Table I: Initial Isolation and Protective Distances
Table III: Large Spills of Toxic Inhalation Hazard Gases
Boiling Liquid Expanding Vapor Explosion (BLEVE) scenarios
The Emergency Response Guidebook is a trusted reference used by first responders and emergency managers to assess hazardous materials and determine protective actions in the initial phase of an incident involving dangerous goods.
The ERG web tool can be accessed from Map Viewer or through the Analysis widget in ArcGIS Experience Builder, making it easily deployable across modern ArcGIS platforms. This tool delivers the functionality previously provided by the Emergency Response Guide widget in ArcGIS Web AppBuilder. As ArcGIS Web AppBuilder is scheduled for retirement in ArcGIS Enterprise in 2025 and ArcGIS Online in 2026, organizations are encouraged to begin migrating to this new tool.
To fully leverage the capabilities of the ERG web tool, there are specific requirements and permissions that must be met.
To create and edit the notebook and publish the web tool, users must have at least a Creator user type with a custom role based on the Publisher role. This custom role should include the following added privileges:
Create and edit notebooks: This privilege allows the user to modify and create ArcGIS Notebooks, which are essential for managing the logic and parameters within the ERG web tool.
Publish web tools: A user needs this privilege to publish custom web tools, such as the ERG web tool, to ArcGIS Online or ArcGIS Enterprise.
To run the ERG web tool, users must have at least a Creator user type with a custom role based on the Publisher role. This custom role must include the following added privilege:
The ERG web tool is a custom tool developed using ArcGIS Notebooks, and like other custom web tools, it consumes credits when run in ArcGIS Online. Credits are consumed based on the time to run the web tool and the runtime level. The ERG notebook uses the Standard runtime. For more information, visit Understand credits for spatial analysis.
Note: There is no credit consumption when the web tool is hosted and run in ArcGIS Enterprise.
The ERG web tool is supported in the following environments:
ArcGIS Online
ArcGIS Enterprise versions 11.3 to 11.5
Requires ArcGIS Notebook Server
To set up the ERG web tool you in your ArcGIS Online or ArcGIS Enterprise, complete the following steps:
Browse to the ERG Materials CSV item page.
Click Download to save the CSV file locally.
Sign into your ArcGIS Online organizational account or ArcGIS Enterprise portal.
At the top of the site, click Content, and then click New Item.
Drag and drop the downloaded erg_materials.csv file.
Choose Add erg_materials.csv only and click Next.
Fill out the item details and click Save.
Sign into your ArcGIS Online organizational account or ArcGIS Enterprise portal.
At the top of the site, click Content, and then click New Item.
Click Feature layer.
Choose Provide an ArcGIS Server layer URL and click Next.
Paste the following URL into the URL parameter: https://services.arcgis.com/P3ePLMYs2RVChkJx/arcgis/rest/services/ERG_Zones/FeatureServer
Click Next three times.
Fill out the item details and click Save.
To host and run the Generate ERG Zones notebook in ArcGIS Online, complete the following steps:
Warning: Adding a notebook by clicking the New Item button will not preserve the required parameters. This workflow will help ensure proper setup.
Browse to the Generate ERG Zones notebook item page.
Sign in with your ArcGIS Online credentials, and then click Open notebook.
Click Save and choose Save as.
Type a title and verify that the Copy parameters to the new notebook option is checked.
Click Save.
Click Parameters to verify that the parameters are saved in the notebook.
Replace the quoted item IDs with the item IDs of the ERG Materials CSV and ERG Zones feature layer in your organization.
8. Click Save to apply the changes.
9. Click Publish.
10. Type a title and description, and then click Publish to publish it as a web tool
To host and run the notebook in ArcGIS Enterprise, complete the following steps:
Browse to the Copy Generate ERG Zones item page.
Click Download to save the notebook file locally.
Sign in to your ArcGIS Enterprise portal.
At the top of the site, click Content, and then click New Item.
Drag and drop the downloaded notebook (2e4afc74fc5944bd8c81256f359cfed9.ipynb).
Fill out the item details and click Save.
From the item page, click Open notebook.
Click Run > Run All Cells to run the notebook.
Running all cells creates a copy of the Generate ERG Zones notebook, including parameters, in your Enterprise portal.
Note: In earlier versions of Enterprise, the command is Cell > Run All.
Scroll down and click the Generate ERG Zones link to open the item page.
On the item page, click the Settings tab, and then in Notebook Settings, set the Notebook Runtime to the version specified in the ArcGIS Notebook Runtime Manifests matrix for your version of Enterprise and click Save.
Click the Overview tab and click Open notebook.
Click Parameters to verify that the parameters are saved in the notebook.
Replace the quoted item IDs with the item IDs of the ERG Materials CSV and ERG Zones feature layer in your portal.
14. Click Save to apply the changes.
15. Click Publish.
16. Type a title and description, and then click Publish to publish it as a web tool
Open ArcGIS Experience Builder and click Create new to create a new app.
Choose a template and click Create.
Add a Map widget to the app.
Note: Learn more about widgets
Tip: Use a web map that includes the ERG Zones feature layer. In Map Viewer, enable Automatically refresh layer on the ERG Zones layer and set the refresh interval to 0.1 minutes to ensure that the map updates when new data is written by the ERG tool.
Add an Analysis widget to the app.
Click Custom web tool in the Analysis widget configuration panel.
In the Select utility panel, click + Add utility > Items and select the published web tool.
Click Done.
Select the web tool in the Select utility pane.
Note: The tool appears in the Analysis widget.
At the top right, click Save, and then click Publish.
Click the vertical dots and click View published item to view the app.
Add a layer: Click Layer to add a layer from the organization.
Draw on the map: Use the Sketch tool to draw it directly on the map.
Use an existing feature: Click the point feature on the web map to open its pop-up. Select Actions > Set as Analysis Input, then complete the dialog to choose the tool and set parameters.
For Material, choose a material by searching by name or placard number, or by selecting it from the drop-down list.
For Spill Size, choose Small or Large.
Note: The Emergency Response Guidebook defines the threshold between a ‘Small and Large’ spill size as 55 gallons (208 liters) for liquids, and 60 pounds (27 kilograms) for solids.
Optionally, enable Show Fire Isolation Zone to create a Fire Isolation Zone.
For Wind Direction (blowing from), provide the wind direction in degrees.
For Time of Spill, choose Day or Night.
Note: The Initial Isolation Zone, Protective Action Zone, and Downwind Zone are generated using the distances specified in Table 1 of the ERG Guide, based on the selected material, time of spill, spill size, and wind direction.
Optionally, enable the Show BLEVE Isolation Zone parameter to create a BLEVE Isolation Zone.
This zone will only be created if it is applicable to the selected material. The size of the BLEVE Isolation Zone will correspond with the chosen container capacity. In the CSV file, applicable materials have a BLEVE column value of “Yes.”
If applicable to the selected material, specify the Wind Speed and Transport Container parameters. These parameters apply only to materials listed in Table 3 of the ERG Guide and are used to determine the size of the Protective Action Zone. In the CSV file, these materials have a Table 3 column value of “Yes.”
Optionally, enable the Append Zones to Feature Layer parameter to append the results to the ERG Zones feature layer.
Optionally, provide an ID in the Analysis ID parameter to help identify this run of the analysis. This ID will be written in the Analysis ID field in the output ERG Zones for reference.
Click Run.
Click the feature generated by the analysis to view its pop-up details.
Click the History tab in the Analysis widget to view the recently executed results.
Click the ellipsis (…) next to a result to access additional details and information.
Under Result, click the Actions button, and then in the Export to item dialog box, click Export.
To stay informed about updates, enhancements, and fixes made to the Emergency Response Guide (ERG) Notebook, review the release notes available on the notebook's item page.
Browse to the Generate ERG Zones notebook item page.
Review the Release Notes section in the item description.