How to Determine Whether an Environmental Zone Applies Only to Commercial Vehicles

Problem

Users may encounter one or more of the following situations:

Environmental Zone (EVZ) XML release information only provides the Environmental Zone name, EZ ID, and country. It does not indicate whether the restriction applies to passenger vehicles, trucks, buses, or multiple vehicle types.
Difficulty identifying if a specific Environmental Zone is relevant for a commercial vehicle use case.
Need to filter Environmental Zone polygons according to vehicle type in mapping or navigation applications.
Requirement to distinguish truck-only zones from passenger-car zones within RDF data.

Quick Answer

The Environmental Zone XML release documentation does not identify whether a zone is restricted to commercial vehicles. To determine applicability, query the RDF data and review the Polygon Restriction value in the RDF_CARTO table, which specifies the vehicle type associated with the Environmental Zone polygon.

Step-by-Step

Environmental Zones can optionally include an Environmental Zone Polygon. The Polygon Restriction attribute in the RDF_CARTO table identifies which vehicle category the polygon applies to and can be used to filter Environmental Zone information based on the user's vehicle profile.
For example, passenger-car users may want to exclude truck-only Environmental Zone polygons from map displays.

Step 1: Understand Polygon Restriction Values

The Polygon Restriction field is published for all Environmental Zone polygons and contains the following values.

| Polygon Restriction Value | Meaning |
| --- | --- |
| 1 | Trucks Only |
| 2 | Autos Only |
| 3 | Autos and Trucks |
| 4 | Buses Only |

These values identify which vehicle category is affected by the Environmental Zone restriction.

Note: Access Characteristics associated with the Environmental Zone condition (CONDITION_TYPE = 34) determine which vehicles are restricted. Polygon Restriction specifically indicates whether the Environmental Zone polygon applies to trucks, passenger cars, buses, or multiple vehicle categories.

Step 2: Query RDF Data for Environmental Zones

Run the following SQL query to retrieve Environmental Zone polygons and their restriction types:

select

rc.carto_id,

rc.polygon_restriction,

rfn2.language_code,

rfn2."name"

from rdf_carto rc

inner join rdf_feature_names rfn

on rfn.feature_id = rc.carto_id

inner join rdf_feature_name rfn2

on rfn2.name_id = rfn.name_id

where rc.feature_type = '9997010';

This query returns:

* Environmental Zone polygon identifier
* Polygon restriction value
* Language code
* Environmental Zone name

Step 3: Filter Environmental Zone Metadata

To retrieve Environmental Zone metadata information, execute:

select *

from rdf_meta rm

where table_name = 'RDF_CONDITION_ENV_ZONE';

This query returns metadata related to Environmental Zone conditions stored within RDF.

Step 4: Validate the Results

After running the query:

1. Locate the target Environmental Zone.
2. Review the polygon_restriction value.
3. Match the value against the restriction table above.
4. Confirm whether the Environmental Zone is:
* Commercial vehicle (truck) only
* Passenger vehicle only
* Applicable to both
* Bus only

Success Criteria

You can successfully determine vehicle applicability when the Environmental Zone record returns a valid polygon_restriction value and the corresponding vehicle category can be mapped using the restriction definitions above.

Searchable Tags / Keywords

Environmental Zone, EVZ, Environmental Zone Polygon, Commercial Vehicle Restriction, Truck Only, Autos Only, Buses Only, Polygon Restriction, RDF_CARTO, RDF_CONDITION_ENV_ZONE, RDF_META, Environmental Zone XML, Vehicle Access Restriction, EZ ID, Environmental Zone Mapping, RDF Query, SQL Query, Vehicle Type Filtering, HERE RDF