users of petrol cars have little to worry about compliance as there is very little difference between bs4 and bs6 fuels the auto industry is set to transition to the bs6 regime in april 2020 in keeping with the supreme courts diktat this is not the first time that manufacturers have had to reconfigure their engines to meet emission control normsthe bharat stage bs norms which are based on european emission standards were initially rolled out in 2000 subsequent iterations bs2 and bs3 came into effect in 2001 and 2005 respectivelyhowever it wasnt until bs4 was implemented that emission levels were capped at levels comparable to global standards in 2016 the government decided to skip bs5 in favour of devising a more stringent standard to check rising pollution from vehicular exhausts advt after much deliberation and extensions it was decided that the final deadline for the implementation of bs6 norms would be april 2020 how is bs6 different from bs4the new emission standard will require both automobile manufacturers as well as oil marketing companies to tweak their respective products for optimal results bs6compliant engines will have to run on bs6 fuel as newgeneration engines running on lower quality fuel will emit a quantum of toxic gases comparable to that generated by bs4 enginesmoreover running bs6compliant vehicles on bs4 fuel could be detrimental to their engines indian oil companies have already established a supply chain for bs6grade petrol and diesel with distribution expanded to most filling stations in new delhi and other metro citiesone of the major differences between bs6 and the incumbent bs4 is that the former contains five times lesser suplhur content 10 parts per million as compared to bs4 50 ppm oxides of nitrogen nox produced as a result of combustion will be brought down by 70 per cent for diesel and 25 per cent for petrol enginesanother significant change will be the presence of obd onboard diagnostics and rde real driving emission on all vehicles enabling realtime tracking of emissions diesel motors will include dpf diesel particulate filter and scr selective catalytic reduction technologies how will manufacturers be affected advt while the transition to cleaner fuels will help bring down harmful pollutants carmakers will have to spend heavily to develop bs6compliant engines for their existing product line the high investment which this entails has deterred many manufacturers like maruti suzuki from developing diesel engines compliant with the new normsmaruti suzuki announced that it will phase out diesel cars from its lineup by april 2020 with the deadline looming large over the horizon prospective buyers are also shying away from diesel models of popular cars adding to the unsold inventory pile of manufacturersthe auto industry which is witnessing a slowdown has to do away with its stock of bs4 vehicles before the supreme courtmandated deadline of april 2020 many manufacturers have indulged in heavy discounting while simultaneously investing in building bs6 fuel compatible engines analysts predict the prices to increase by 10 per cent with carmakers passing on