Here BS standards are explained with history. BS IV- norms for two wheeler, three wheeler and implementation dates BS IV- norms for above and implementation dates Also ARAI figures also attached. Edited by Aditya Deshpande deshadi805@gmail.com

1. Bharat Stage Norms – History and Future – Edited by Aditya Deshpande (20170203)
Report on
Bharat Stage Norms – History and Future
Edited by
Mr. Aditya Deshpande
(142130)
Automobile Engineering
Department of Mechanical Engineering
Vishwakarma Institute of Technology, Pune
Pune-411037
February 2017

2. Bharat Stage Norms – History and Future – Edited by Aditya Deshpande (20170203)
Bharat Stage IV Standards
Bharat Stage IV standards for 2-wheeled gasoline vehicles (motorcycles) were adopted in July
2014. BS IV standards introduced several new requirements, including:
1. Tightened NOx+HC emission limits.
2. Harmonization of the emission testing cycle and the definition of motorcycle classes
with the UNECE Global Technical Regulation 2 (GTR-2). Beginning with BS IV
standards, emissions are tested over the Worldwide Harmonized Motorcycle Test Cycle
(WMTC).
3. First-ever evaporative emission standards.
The definitions of vehicle categories and test requirements are shown in Table 2. BS IV
emission standards are summarized in Table 3.
The BS IV regulation also included emission standards for mopeds with D ≤ 50 cc and Vmax ≤
50 km/h. The applicable limits are:
 CO = 0.75 g/km
 HC+NOx = 0.75 g/km
Table 2
BS IV 2-wheel vehicle classification and testing requirements
Class Definition* Test Cycle†
Class 1 50 < D < 150 cc and
Vmax ≤ 50 km/h
or
D < 150 cc and
50 < Vmax < 100 km/h
Part 1 reduced speed cold [0.5] +
Part 1 reduced speed hot [0.5]
Class 2-1 D < 150 cc and
100 ≤ Vmax < 115 km/h
or
D ≥ 150 cc and
Vmax < 115 km/h
Part 1 reduced speed cold [0.5] +
Part 1 reduced speed hot [0.5]
Class 2-2 115 ≤ Vmax < 130 km/h Part 1 cold [0.3] + Part 2 hot [0.7]
Class 3-1 130 < Vmax < 140 km/h Part 1 cold [0.25] + Part 2 hot [0.5] +
Part 3 reduced speed [0.25]
Class 3-2 Vmax ≥ 140 km/h Part 1 cold [0.25] + Part 2 hot [0.5] +
Part 3 [0.25]
* Abbreviations: D - engine displacement; Vmax - maximum design speed.
† WMTC phase sequence. Values in square brackets are weighting factors.

3. Bharat Stage Norms – History and Future – Edited by Aditya Deshpande (20170203)
Table 3
BS IV emission standards for 2-wheel gasoline vehicles, g/km
Date* Class CO NOx
HC+NOx†
SHED ≤ 2 g SHED ≤ 6 g
2016.04 Class 1
& 2-1
1.4
03
0.39 0.79 0.59
Class 2-
2
1.9
70
0.34 0.67 0.47
Class 3-
1 & 3-2
1.9
70
0.20 0.40 0.20
* New type approvals—all models one year later.
† The limit depends on the result of the evaporative emission test (SHED).

4. Bharat Stage Norms – History and Future – Edited by Aditya Deshpande (20170203)
Bharat Stage VI Standards
Bharat Stage VI standards for 2- and 3-wheeled vehicles were proposed in February
2016 (skipping the BS V stage). The proposed limits, Table 4, apply to new model 2-wheeled
vehicles and all models of 3-wheeled vehicles. These proposed standards align with Euro 5
limits for these vehicles.
Table 4
Proposed BS VI emission standards for 2- and 3-wheel vehicles, g/km
Date Stage Type CO HC NMHC NOx PM
2-Wheel Vehicles (new models only)
2020.04 BS VI SI 1.0 0.10 0.068 0.06 0.0045*
CI 0.50 0.10 0.068 0.09 0.0045
3-Wheel Vehicles (all models)
2020.04 BS VI SI 0.44 0.35 - 0.085 -
CI 0.22 0.10 - 0.10 0.025
* Gasoline direct injection only
The BS VI emission standards, Table 4, include a 35,000 km durability and Stage II OBD
requirements. Spark ignition vehicles must additionally meet an evaporative emission limit of
1.5 g/test.
The BS VI regulation also includes emission standards for 2-wheelers with an SI engine and D
≤ 50 cc and Vmax ≤ 50 km/h. The applicable limits are:
 CO = 0.50 g/km
 HC = 0.35 g/km
 NOx = 0.15 g/km
In November 2015, a draft proposal was published that required vehicles compatible with
biodiesel blends up to B100 to certify with both diesel fuel and B100.

5. Bharat Stage Norms – History and Future – Edited by Aditya Deshpande (20170203)
Emission Norms for Two and Three Wheelers
In 1991 when the emission control regime started in India, the norms for 2 wheelers started
with the only then existing UNECE regulation (R40) but with an India specific Indian Driving
Cycle (IDC). Subsequently, these norms were progressively tightened. BS III emission norms
are about 7% for CO and 10% for HC + NOx of the norms introduced in 1991. Emission norms
from BS I (2000) to the proposed BS IV norms for 3 wheelers has seen a reduction of 75% for
CO and 47% for HC + NOx for SI engines. The order of reduction is similar to what transpired
in Europe’s Tricycles over 17 years where the permissible limits were reduced by 85%.
Over and above tightening the CO, HC + NOx limits, a deterioration factor of 1.2 was
introduced in the year 1998. From the year 2000 onwards, a relaxation of 20% given for
conformity of production (CoP) was removed by the Government, which led to maintenance
of very strict production control with minimum variations.
Type of Test:
 Type I Test: Exhaust Emission (IDC)
 Type II Test: Spark Ignition Idle CO & HC Compression Ignition Test (3 wheelers) - Free
Acceleration Smoke
 Type III Test: The durability of Anti-Pollution Device is determined either by an actual
durability run over 30000 km or by application of a fixed deterioration factor.
Driving Cycle: Type I Test: 6 Cycles
Mass emission standards (Bharat Stage III) for Two & Three Wheelers
As per Government Notification GSR 84 (E) 2009 and GSR 443 (E) 2010, the Emission
Standard for 2 wheeler and 3 wheeler applicable in all the States and the Union Territories
except National Capital Region and the cities of Mumbai, Kolkata, Chennai, Bangalore,
Hyderabad including Secunderabad, Ahmedabad, Pune, Surat, Kanpur, Agra, Sholapur, and
Lucknow in respect of 2 wheelers and 3 wheelers manufactured on or after 1st October 2010.

6. Bharat Stage Norms – History and Future – Edited by Aditya Deshpande (20170203)
Vehicle
Category
Pollutants
Type Approval (TA) =
Conformity of
Production (COP) Norms
(g/km)
D.F.
(Deterioration
Factor)
Two Wheeler
(Gasoline)
CO 1.00 1.20
HC + NOx 1.00 1.20
Three Wheeler
(Gasoline)
CO 1.25 1.20
HC + NOx 1.25 1.20
Two-wheelers
and Three
Wheeler
(Diesel)
CO 0.50 1.00
HC + NOx 0.50 1.00
PM 0.50 1.20
For gasoline two-wheelers, other than mopeds, WMTC is applicable for setting the BS III, BS
IV and BS V Two Wheeler emission norms. The Government had notified Worldwide
Harmonized Motorcycle Emissions Certification (WMTC) vide G.S.R. 515(E), 29th June,
2012. Please note that WMTC is optional. Some of manufacturers depending upon their
facilities are following this cycle.
Class, Driving Cycle and Weighting factors:
Class Definition of Class Cycles
Weighting factors for final
emission results
Class
1
Engine capacity above 50cc but
less than 150cc and vehicle
maximum speed equal to or less
than 50 km/h OR engine
capacity less than 150 cc an.
vehicle maximum speed more
than 50 km/h but less than 100
km/h.
Part 1 Reduced
Speed cold
followed by
Part 1 Reduced
Speed Hot
Part 1 Reduced Speed cold
shall be 50 % and Part 1
Reduced Speed Hot shall be
50 %

7. Bharat Stage Norms – History and Future – Edited by Aditya Deshpande (20170203)
Sub
Class
2.1
Engine capacity less than 150 cc
and vehicle maximum speed
equal to or more than 100 km/h
but less than 115 km/h OR
engine capacity 150 cc and
above and vehicle maximum
speed less than 115 km/h
Part 1 Reduced
Speed cold
followed by
Part 1 Reduced
Speed Hot
Part 1 Reduced Speed cold
shall be 50 % and Part 1
Reduced Speed Hot shall be
50 %
Sub
Class
2.2
Any engine capacity and vehicle
maximum speed equal to or
more than 115 km/h but less
than 130 km/h
Part 1 cold
followed by
Part 2 Hot
Part 1 cold and shall be 30%
and Part 2 Hot shall be 70 %
Sub
3.1
Any engine capacity, vehicle
maximum speed equal to or
more than 130 km/h but less
than 140 km/h
Part 1 cold
followed by
Part 2 Hot
followed by
Part 3 Reduced
Speed
Part 1 cold shall be 25%; Part
2 Hot shall be 50% And Part
3 Reduced shall be 25 %
Sub
Class
3.2
Any engine capacity and vehicle
maximum speed equal to or
more than 140 km/h
Part 1 cold
followed by
Part 2 Hot
followed by
Part 3
Part 1 cold shall be 25%; Part
2 Hot shall be 50% And Part
3 shall be 25%
Alternate Mass Emission Standards (Bharat Stage III) for two wheeler gasoline vehicles, with
engine capacity exceeding 50cc or a maximum design speed exceeding 50 km/hour, based on
WMTC procedure shall be as under table.
Class Pollutants
TA=COP norms
including Deterioration
Factor (g/km)
Class 1
and Sub
Class 2.1
CO 1.87
HC+NOx 1.08
Sub Class
2.2
CO 2.62
HC+NOx 0.92

8. Bharat Stage Norms – History and Future – Edited by Aditya Deshpande (20170203)
Sub Class
3.1
CO 2.62
HC+NOx 0.55
Sub Class
3.2
CO 2.62
HC+NOx 0.55
Three Wheeler Emission Norms for Spark Ignition and Compression Ignition Engines
Mass emission standards (Bharat Stage IV) for Two Wheelers
The Government of India released the latest notification GSR 431 (E) 4th July 2014 regarding
Mass Emission Standards (BS IV) which shall come into force for Two wheelers manufactured
on and after the 1st April, 2016 for new types of vehicle models and from the 1st April, 2017
for existing types of vehicle models-
Two Wheeled Vehicles fitted with Gasoline Engines:
Mass emission standards (Bharat Stage IV) for two wheelers, with engine capacity exceeding
50 cc and a maximum design speed exceeding 50 km per hour, based on World-wide
Harmonized Motorcycle Test Cycle (WMTC)

9. Bharat Stage Norms – History and Future – Edited by Aditya Deshpande (20170203)
Class
TA=COP norms (g/km)
CO NOx HC + NOx
If the evaporative
emission complies
with 2 g/test
If the evaporative
emission complies
with 6 g/test
Class 1 and
Sub-class 2-1
1.403 0.39 0.79 0.59
Sub-class 2-2 1.970 0.34 0.67 0.47
Sub-class 3-1
and -class 3-2
1.970 0.20 0.40 0.20
Mass emission standards (BSIV) for two wheelers with Spark Ignition engines Vehicles
with cc < 50 and Vmax < 50 km/hr.):
Pollutant
TAP=COP
norms (g/km)
Deterioration
Factor (DF)
CO 0.75 1.20
HC + NOx 0.75 1.20

10. Bharat Stage Norms – History and Future – Edited by Aditya Deshpande (20170203)
Two Wheeled Vehicles fitted with Diesel Engines:
The mass emission standards shall be same as those applicable for diesel three-wheelers.
Proposed (Bharat Stage V) Emission Norms for Indian Two Wheelers
As per Report of AFV&P 2025, May 2014, BS V Emission norms are proposed with a further
emission reduction over BS IV norms. The values are given below for Gasoline two wheelers
of Classes 1, 2 & 3. The details are given below. BS V emission norms for two wheelers in
India will be applicable four years after the implementation of BS IV emission norms for two
wheelers.
Vehicle Class
BS V Emission Norms
CO g/km HC + NOx g/km NOx (g/km)
1 & 2-1 1.140 0.450 0.225
2-2 1.140 0.450 0.225
3-1 & 3-2 1.140 0.260 0.130
DF (for all classes) 1.300 1.200 1.200
Note: Applicable for new models from 1 April 2020 and existing models from 1 April 2021.

11. Bharat Stage Norms – History and Future – Edited by Aditya Deshpande (20170203)
The CO limits are significantly tighter than BS IV limits; that for HC and NOx are combined
with a separate sub-limit for NOx. Indian two wheelers are one Emission Norms for Three
Wheeler for BS IV and BS V Regimes of the best in the world on fuel economy. This superior
fuel economy has been achieved mainly by designing the engines with lean mixture (air fuel
ratio is considerably above stoichiometric ratio). Use of lean mixture ratio, while improving
the fuel efficiency and CO emissions tend to increase NOx emission. Therefore, in order to
control the likely NOx emissions from two wheelers, an additional limit for NOx is being
proposed within the overall limit of HC + NOx. However, this may limit the extent of fuel
efficiency that can be achieved from two wheelers in future.
BS V Emission Norms Two Wheelers with cc < 50 and Vmax < 50 km/h and Diesel Two
Wheelers
As per Report of AFV&P 2025, May 2014, since these classes of two wheelers are not being
produced in India, it is recommended that these norms may be developed by the concerned
Ministry, as and when their production in India becomes significant or when such norms are
included in GTR based on the Environmental and Propulsion Performance Requirements
(EPPR).

12. Bharat Stage Norms – History and Future – Edited by Aditya Deshpande (20170203)
Emission Norms for Indian 3-Wheelers for BS-IV and BS-V
Proposed Emission Standards (Bharat Stage IV) for Three Wheelers
As per Report of AFV&P 2025, May 2014, BS III emission norms for 3-wheelers were notified
vide GSR 84(E)/9 February 2009 and implemented from 1 April 2010 in some parts of country
and from 1 October 2010, all over India. It is proposed that the BS IV emission norms for 3-
wheelers be as given in the table below. They will become effective from 1 April 2016.
Three Wheeler Emission Norms for SI and CI Engines – BS IV
Spark Ignition (SI) Engines - Gasoline / CNG / LPG
BS-III BS-IV
Test cycle and test
procedureCO HC + NOx CO
HC + NOx
Option 1 Option 2
Limits 1.25 1.25 0.94 0.94 0.74
IDC BS III TAP
DF 1.20 1.20 1.20 1.20 1.20
Compression Ignition (CI) Engines - Diesel
BS-III BS-IV Test cycle
and test
procedureCO HC + NOx PM CO
HC +
NOx
PM
Limits 0.50 0.50 0.50 0.38 0.38 0.0425 IDC BS III
TAPDF 1.10 1.00 1.20 1.10 1.00 1.20
Note:
1. For Three Wheeler gasoline engines, evaporative emissions are applicable and the base
case limit value is 2g/test.
2. Option 2 is applicable, if Evaporative Emission norm of 6 g/test is complied with.
3. For vehicle with CNG/LPG application, current practice of factoring NMHC and RHC
emission will continue and evaporative emission tests are not applicable.
4. BS IV norms to be applicable from 1st April 2016.
Emission Norms for Indian 3-Wheelers for BS-V
As per Report of AFV&P 2025, May 2014, with the implementation of BS IV emission norms,
Indian 3-wheelers, which are predominantly carburetted, will be tuned for lean operation which
will keep the fuel efficiency as high as possible. Any further reduction in the NOx limits would
not be possible with carburetted technology. A shift will have to be made towards adoption of
stoichiometric ratio and the use of a 3-way catalytic converter will be needed in the case of SI
engine.
For CI engines, further reduction in emissions beyond proposed BS IV emission norms will
require the incorporation of technologies such as Turbo Charger, High pressure injectors,

13. Bharat Stage Norms – History and Future – Edited by Aditya Deshpande (20170203)
Sensors and ECU to improve engine efficiency which have not been developed. The proposal
for BS V emission norms for 3-wheelers is given at table below:
Spark Ignition (SI) Engines - Gasoline / CNG / LPG
BS-IV BS-V
Test cycle and
test procedureCO
HC + NOx
CO HC + NOx
Option 1 Option 2
Limits 0.94 0.94 0.74 0.66 0.66
IDC BS III TAP
DF 1.20 1.20 1.20 1.20 1.20
Compression Ignition (CI) Engines - Diesel
BS-IV BS-V
Test cycle and
test procedure
CO HC + NOx PM CO HC + NOx PM
Limits 0.38 0.38 0.0425 0.26 0.26 0.038
IDC BS III TAP
DF 1.10 1.00 1.20 1.10 1.00 1.20
Note:
1. For Three Wheeler gasoline engines, evaporative emissions are applicable and the base
case limit value is 2g/test
2. Option 2 is applicable, if Evaporative Emission norm of 6 g/test is complied with.
3. For vehicle with CNG/LPG application, current practice of factoring NMHC and RHC
emission will continue and evaporative emission tests are not applicable.
4. BS V norms to be applicable from 1st April 2020 for new models and 1 April 2021 for
existing models.
From April 1, 2016, all new models of two-wheelers will need to comply with BS-IV
norms, while existing models launched until March 31, 2016 need to upgrade to BS-IV
by April 1, 2017.
Following pages contains ARAI Charts and values for pollution control Bharat Stages.

14. Bharat Stage Norms – History and Future – Edited by Aditya Deshpande (20170203)
ARAI BS IV TWO WHEELERS

15. Bharat Stage Norms – History and Future – Edited by Aditya Deshpande (20170203)

16. Bharat Stage Norms – History and Future – Edited by Aditya Deshpande (20170203)

17. Bharat Stage Norms – History and Future – Edited by Aditya Deshpande (20170203)

18. Bharat Stage Norms – History and Future – Edited by Aditya Deshpande (20170203)