BS IV standards (based on Euro 4) applied to all new vehicles nationwide in April 2017. BS VI standards (based on Euro 6) apply to all new vehicles nationwide starting in April 2020. Like heavy-duty vehicles, these standards leapfrogged from Euro IV-equivalent directly to Euro VI-equivalent standards.
Conventional pollutant emission limits
The body that is primarily responsible for setting emissions and efficiency standards is the Ministry of Road Transport and Highways (MoRTH). Further detail regarding India’s regulatory bodies can be found on the India Regulatory Background page. Other regulatory agencies responsible for fuel and environmental regulations are below.
- Central Pollution Control Board (CPCB)
- Ministry of Petroleum and Natural Gas (MoPNG)
- Ministry of Environment and Forest (MoEF)
- Bureau of Indian Standards (BIS)
Light-duty vehicles GVW ≤ 3,500 kg including passenger cars, utility vehicles, vans and light commercial vehicles
Starting with court rulings in the late 1980’s and 1990’s, India began to lower its permissible vehicular pollution emission limits for four-wheelers. After 2000, India adopted the European template for vehicle emissions standards, creating parallel ‘Bharat’ standards (e.g. Bharat III standards are equivalent to Euro 3 standards). New vehicles sold in select Indian cities must meet Bharat IV (Euro 4) standards, while the rest of the country mandates Bharat III standards.
Important legislative milestones include:
- The Air (Prevention and Control of Pollution) Act of 1981 and the Environment (Protection) Act of 1986 gave government the right to regulate motor vehicle emissions.
- The Motor Vehicles Act of 1988 established vehicular emission standards and authorized the central government and state governments to further regulate and enforce them.
The Auto Fuel Policy of 2003 set a roadmap for progressively tighter heavy-duty vehicle emission standards through 2010, which is currently still in force. This policy aligned Indian emission standards with the European model.
The Auto Fuel Policy of 2003 also laid out two different sets of standards, one for select cities and one for the rest of the country. The timeline of advanced standards for India’s main cities is summarized in the following table.
a – Proposed implementation date
b – 24 Oct 2000 for Delhi; 21 Oct 2001 for Mumbai, Kolkata and Chennai
Bharat Stage VI
On 19 Feb 2016, the Ministry of Road Transport and Highways (MoRTH) issued a draft notification of Bharat Stage (BS) VI emission standards. The standards, as proposed, will take effect throughout the country for all light-duty and heavy-duty vehicles as well as two and three wheelers manufactured on or after 1 Apr 2020. The draft proposal specifies mass emission standards, type approval requirements, and on-board diagnostic (OBD) system and durability levels for each vehicle category. The proposal also specifies changes to vehicle type approval procedures for light-duty vehicles by including provisions for in-service conformity testing using portable emissions measurement system (PEMS).
The proposed BS VI regulation establishes an important precedent for leapfrogging from Euro IV-equivalent directly to Euro VI-equivalent motor vehicle emissions standards.
Emission standards for light-duty vehicles (GVW ≤ 3,500 kg) are summarized below. The lowest limit in each range applies to passenger cars (GVW ≤ 2,500 kg; up to 6 seats).
Regulated pollutants include hydrocarbons (HC), carbon monoxide (CO), oxides of nitrogen (NOx), and particulate matter (PM), which are tested using a modified version of the European NEDC test cycle. The main difference between the European and Indian testing cycles is that the Indian test has a maximum speed of 90 km/h, while the European has a maximum speed of 120 km/h.
|2000||India Stage I||2.72-6.90||–||0.97-1.70||–||0.14-0.25||–|
|2005†||Bharat Stage II||1.0-1.5||–||0.7-1.2||–||0.08-0.17||–|
|2010†||Bharat Stage III||0.64
|2017‡||Bharat Stage IV||0.50
|2020||Bharat Stage VI+||0.50
|2000||India Stage I||2.72-6.90||–||0.97-1.70||–||–||–|
|2005†||Bharat Stage II||2.2-5.0||–||0.5-0.7||–||–||–|
|2010†||Bharat Stage III||2.3
|2017‡||Bharat Stage IV||1.0
|2020||Bharat Stage VI+||1.0
|Note: When three limits are listed, they refer to vehicles category M & N1 Class I, N1 Class II, and N1 Class III, respectively.
* for catalytic converter fitted vehicles
† earlier introduction in selected regions; see first table
‡ only in selected regions; see first table
+ Proposed limits
a – and NMHC = 0.068 g/kWh
b – and NMHC = 0.090 g/kWh
c – and NMHC = 0.082 g/kWh
d – For PI engines, PM and particle number (PN) limits apply only to direct injection engines
e – Manufacturers can opt to meet a PN limit 6x1012/kWh to compliance for the first three years from the date of implementation for new type approvals and sales
Gasoline vehicles must also meet an evaporative (SHED) limit of 2 g/test (effective 2000). Through the Bharat II (Euro II) stage, engines for use in light-duty vehicles could be alternatively tested using an engine dynamometer. The respective emission standards are listed below.
|* 0.612 for engines below 85 kW
† earlier introduction in selected regions
OBD I is required from 1 Apr 2010 (except LPG or CNG-fuelled vehicles and those >3500 kg GVW). OBD II is required from 1 Apr 2013 for Bharat Stage IV light-duty vehicles of all categories.
BS VI draft proposes introduction of OBD requirements in two phases, with preliminary OBD thresholds applicable (BS VI-1 OBD) all vehicles manufactured on or after 1 Apr 2020, and final thresholds (BS VI-2 OBD) applicable from 1 Apr 2023. The proposed threshold values for BS VI-1 OBD and BS VI-2 OBD are equivalent to preliminary and final Euro 6 threshold limits, respectively. The BS VI OBD threshold values are specified in the table below.
|BS VI-1||1 Apr 2020||Positive Ignition||1.90||0.170||0.15||0.025*|
|BS VI-2||1 Apr 2023||Positive Ignition||1.90||0.170||0.09||0.012a|
|Note: The three limits listed refer to vehicle categories M and N1 Class I, N1 Class II and N1 Class III, respectively.
*For positive Ignition engines, PM limits apply only to direct ignition engines
a – PM limit for N1 Class I specified as 0.025 g/kWh
Under Bharat III and IV specifications, fuel used to test emissions from vehicles is cleaner than commercially available fuel. Regulations specify that Bharat IV test diesel can have a maximum sulfur content of 10 ppm, while commercial diesel contains up to 50 ppm and 350 ppm sulfur in Bharat IV cities and the rest of the country, respectively. The lower sulfur content of test fuel means that emissions measurements during testing are lower than real-world emissions on the road, particularly for PM. The full diesel and petrol specifications for test fuels may be found in the ARAI Indian Emission Regulation Booklet.
BS VI fuel specifications apply a 10 ppm sulfur limit to both test fuel and commercially available diesel and gasoline. The Ministry of Petroleum and Natural Gas (MoPNG) announced nationwide supply of BS VI fuel in conjunction with the proposed BS VI emission standard implementation date of 1 Apr 2020. For details on fuel specifications for BS VI, see India: Fuels: Diesel and Gasoline.
BS VI follows Euro VI specifications for the durability of pollution control devices. Manufacturers may either use the deterioration factors specified in the standard or evaluate deterioration factors using a vehicle or bench aging test with a minimum distance requirement of 160,000 km.
Questions or updates about policies?