# Average Speed for Isochrones. Emergency vehicles **URL:** https://ask.openrouteservice.org/t/average-speed-for-isochrones-emergency-vehicles/1521 **Category:** isochrones **Created:** [March 27, 2020, 9:16am UTC](https://ask.openrouteservice.org/t/average-speed-for-isochrones-emergency-vehicles/1521 "2020-03-27T09:16:07Z") **Posts on this page:** 1 **Showing post:** 3
### Author: ![andrzej](https://ask.openrouteservice.org/user_avatar/ask.openrouteservice.org/andrzej/32/10_2.png) [@andrzej](https://ask.openrouteservice.org/u/andrzej) #### Post date: [March 27, 2020, 10:21am UTC](https://ask.openrouteservice.org/t/average-speed-for-isochrones-emergency-vehicles/1521/3 "2020-03-27T10:21:52Z")
Dear Robin, dear Nils, I think you are talking about two slightly different things. What Robin needs is the option to increase the average speed, possibly even over the legal limit. What @nils is referring to, however, is the maximum speed limit which sets a certain threshold while still obeying any legal limits or restrictions based on road classification. Unfortunately, we currently don’t offer a solution to the former. The latter feature is indeed in our development pipeline and will be released soon. It will allow you to select a certain maximum speed, say 80km/h on roads which normally have a higher speed assignment based on legal situation and road properties. For more details see [#480](https://github.com/GIScience/openrouteservice/issues/480). @Robin, in order to address your use case you would probably need to implement a dedicated emergency profile based on the [`VehicleFlagEncoder`](https://github.com/GIScience/openrouteservice/blob/master/openrouteservice/src/main/java/org/heigit/ors/routing/graphhopper/extensions/flagencoders/VehicleFlagEncoder.java), you might use [HGV](https://github.com/GIScience/openrouteservice/blob/master/openrouteservice/src/main/java/org/heigit/ors/routing/graphhopper/extensions/flagencoders/HeavyVehicleFlagEncoder.java) as a template. Cheers, Andrzej --- _[View the full topic](https://ask.openrouteservice.org/t/average-speed-for-isochrones-emergency-vehicles/1521)._