When considering retrofitting your vehicle, it is important to make sure that you get the right retrofit to allow you entry into the Low Emission Zones you need.

 
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Which Countries allow Retrofitting?

More information is available from the pages on the individual LEZs, and each LEZs' own websites, but in general in terms of fitting particulate filters:

In Austria you can retrofit some lorries with a particulate filter to meet the emissions standards. Find out here which companies offer retrofitting in Austria.

In Germany you can retrofit to Euro 2, 3 or 4 with a particulate filter. Find out here which companies offer retrofitting in Germany.

In the Netherlands since July 2013 the full Euro 4 standard is required to access to the environmental zones, and retrofitted vehicles are no longer allowed. 

In London, vehicles can be retrofitted as long as the retrofit device is certified as meeting the required emissions standard of Euro 4 in 2012. Only full filters are certified in London. Find out here and here which companies offer retrofitting in London.

In Denmark, particulate filters should be fitted on Euro 3 or earlier vehicles after 2010. Only full filters are certified in Denmark. Find out here which companies offer retrofitting in Denmark.

In most Italian low emission zones particulate filters can be fitted to allow access. However, this depends on the individual city. Find out here which companies offer retrofitting in Italy.

In Sweden retrofitting is allowed if you meet fit both a particulate filter and SCR to meet the required standard. Find out here which companies offer retrofitting in Sweden.