The BS4 emission norms will come into full effect from April 2017 and sale as well as registration of any vehicles that does comply with this standard will not be permitted to ply on the roads. The Road Transport Ministry has already issued a draft notification for making BS4 norms mandatory across the country in a phased manner from October onwards.
The draft notification adds that the BS4 standard shall come into effect with regard to four-wheeled vehicles manufactured on or after April 2017. The emission norm is already in place in all the major metros and from this October will come in to effect in J&K (expect Leh and Kargil), Punjab and Haryana, Himachal Pradesh, Uttarakhand and most districts of UP and Rajasthan. The second stage of full implementation will see it come into effect in Kerala, Karnataka, Telagana, Daman & Diu, Dadra & Nagar Haveli, Andaman & Nicobar, Thane, Pune, Surat, Valsad, Dang and Tapi.
The draft notification says this change will, for the present, not apply to interstate vehicles, national permits and all-India tourist permits. They come under the purview of the notice from April 2017.