How we built a map showing monthly ISA data update in EU

As of July 2022, Intelligence Speed Assistance (ISA) is mandatory in the European Union, Norway, and Switzerland on all new-model cars, vans, trucks, and buses. ISA systems source speed limits from on-vehicle sensors, like cameras, which can read speed signs. However, up to 60% of speed limits are not explicitly signposted and are based on implicit signs and would require the freshest map data. Implicit speed limits are road signs that do not show a numerical value (administrative areas, for example) but are based on existing rules and regulations. 

The HERE ISA Map aims to show the percentage of the road network that has been updated by country and month.

Data

This map visualization is based on the data available in the HERE ISA Map and shows the number of monthly map updates in km by the length of the road network across 27 European Union country members, Switzerland and Norway between August 2019 and March 2022. The map also shows more detailed information for each country, such as the split between implicit and explicit speed limit updates, as well as the percentage of a country’s road network with allowed driving speeds.

User Experience and UI

Data on the percentage of the road network that has been updated in a given month is displayed using a thematic choropleth map, where darker shades indicate more changes for the given month.

Users can also see at a glance the absolute number of km that was updated in a given month, and switch the month by moving the slider. More detailed information on a specific country is also available. Users can get information on the split between explicit and implicit updates in a specific country for a given month. Additional information on the percentage of road networks with allowed driving speeds is also displayed in a donut chart.

Embedding the map

The map can be embedded as an iframe, with detailed instructions for desktop and/or mobile devices available under the About modal.

HERE data and products used

This map is based on HERE ISA Map, a reliable and up-to-date speed limit data source for ISA systems. We also used the HERE Javascript API to render the map. 

Read more about what is ISA and driving safety with ISA.