BS-IV vs BS-VI: What you need to know

Published On : 03 January 2020
By Tarashekhar Padhy


After the confirmation of the new BS-VI emission regulations, major automakers are working hard to launch their new vehicles with BS VI-compliant engines or upgrade their existing vehicles with BS-VI power units. But why is BS-VI so important and in what ways it is different from BS-IV?


BS-VI (or BS6), is an abbreviation Bharat Stage Emission Standards. These are enforced by the govt of India to manage the expelled pollutants from automobiles. The Central Pollution control panel, which is governed by the Ministry of Environment, Forest and global climate change sets the quality for these emissions.


Bharat Stage Emission Standards were initially introduced in the year 2000 as 'India 2000'. They were followed by BS2 and BS3 in 2005 and 2010 respectively, while the continued BS4 standards were enforced in 2017. However, considering the increasing need to make emission norms stricter, the govt. has decided to imply BS6 norms directly, skipping BS5 within the method.


BS6 compliant gasoline automobiles are compulsatory to be 25 percent cleaner by decreasing NOx (Nitrogen Oxide) emissions from 80mg/km to 60mg/km. For diesel vehicles, the BS6 norms target to reduce the three emission wastes which consist of HC (Hydrocarbons) + NOx, PM (Particulate Matter) and NOx minimization by 43, 68 and 82 percent respectively.