commiss direct novemb adapt technic progress council direct februari approxim law member state relat permiss sound level exhaust system motor vehicl eec commiss european commun regard treati establish european econom commun regard council direct februari approxim law member state relat type approv motor vehicl trailer eec amend act annex treati access member state eec eaec sign brussel januari articl thereof regard council direct februari approxim law member state relat permiss sound level exhaust system motor vehicl eec amend act annex treati access member state eec eaec sign brussel januari articl thereof vehicl design built sound level exce prescrib limit principl appli exhaust system silenc light technic progress test exhaust system condit correspond normal oper state road traffic consequ method adopt enabl type silenc test condit test silenc effect continu road test special bench test effect continu road oper produc doubt recours test bench provis direct conform opinion committe adapt technic progress direct remov technic barrier trade motor vehicl sector adopt direct articl annex council direct februari eec head ii entitl quot exhaust system silenc quot replac text contain annex present direct oj oj pp oj articl effect march member state ground relat permiss sound level exhaust system refus eec type approv deliveri document refer articl indent council direct februari eec nation type approv type motor vehicl prohibit entri servic vehicl sound level exhaust system type vehicl vehicl compli provis council direct februari eec amend direct effect octob member state longer issu document envisag articl indent council direct februari eec type vehicl sound level exhaust system compli provis council direct februari eec amend direct refus nation type approv type vehicl sound level exhaust system compli provis council direct februari eec amend direct effect octob member state prohibit entri servic vehicl sound level exhaust system compli provis council direct februari eec amend direct member state adopt publish provis order compli direct march forthwith inform commiss thereof articl direct address member state brussel novemb commiss presid françoi xavier ortoli annex ii exhaust system silenc ii vehicl fit devic design reduc exhaust nois silenc requir contain head ii met engin air intak fit air filter order conform permiss nois level filter consid form part silenc requir head ii appli filter ii diagram exhaust system append type approv certif vehicl ii silenc bear legibl indel indic mark type ii fibrou absorb materi construct silenc suitabl measur undertaken design product stage ensur effici compli limit impos head achiev road silenc consid effici road ii silenc prototyp vehicl test accord requir item put normal state road nois level measur carri ii continu oper road km ii half oper consist town drive half longdist run high speed continu oper road replac programm track test ii care altern time rang road speed ii complet test programm includ minimum break hour durat order reproduc effect cool condens occur ii bench test condit ii standard part observ vehicl manufactur instruct silenc fit engin coupl dynamomet ii test perform hour period break hour period order reproduc effect cool condens occur ii hour period engin run success condit minut sequenc idl speed hour sequenc load peak power speed hour sequenc load peak power speed ten minut sequenc full load peak power speed fifteen minut sequenc load peak power speed thirti minut sequenc load peak power speed phrase quot peak power speed quot mean quot manufactur total length sequenc hour period compris set sequenc ii test silenc cool forc draught simul slipstream vehicl cool author request manufactur order exce temperatur record silenc inlet vehicl travel maximum speed ii remov fibrou matter silenc ii condit silenc item ii nois measur carri conform requir item measur nois level exce laid item categori vehicl belong ii case articl council direct quot type approv quot appli method test item ii valid method ii suitabl attach ensur fibrou absorb materi remain posit oper life silenc