06/12/2011 : UK releases Final Report on Feasibility of a NOx Retrofit Certification Scheme
UK's Defra released the final version of their study investigating the feasibility of a NOx Retrofit Certification Scheme for heavy-duty vehicles

05/12/2011 : Hungary issues Rules for Heavy-duty DPF Retrofits
Hungary has notified the European Commission of rules for retrofit particulate filters for heavy-duty vehicles, particularly coaches