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BS6 vs BS4 vs BS3 vs BS2 vs India 2000: Emission Norms Compared

BS6 is gonna roll out in less than 10 days from now. People are a bit sceptical about the BS6 roll out as right now all the automotive companies are facing huge problems due to Coronavirus pandemic. We have to wait until the end of the month to see what BS6 has to offer. But before that here is a glimpse of where the emission norms started.

Bharat Stage Emission Standards (BSES)

BSES are the emission standards set by the institute by the Government of India which are to put exhaust emission from vehicles in check. These include all the vehicles running via an internal combustion engine on road, trucks, cars, motorcycles, etc.

  • These emission standards are based on the norms in Europe also called Euro Stages. The first regulation was implemented in the year 2000 and was called ‘India 2000’.
  • After that different emission norms came and the latest emission norms are the BS6 implementation from the 1st of April.
  • BS2 or Bharat Stage 2 was implemented in 2001 in the major cites and later in 2005, it was implemented nationwide.
  • In 2005 the BSES implemented BS3 in major cities like Mumbai, Delhi, Kolkata and later in the year 2010 nationwide.
  • Implementing the first major change was a task. As the new BS4 norms had to reduce pollution by a drastic amount. This was done after nearly a decade. BS4 norms were implemented in April 2017 nationwide.

What do BS2, BS3, BS4 and BS6 represent?

The Indian government established Bharat Stage (BS) norms as vehicle emission standards for pollution control purposes. The new stage establishes more severe requirements for toxic emissions than previous stages.

  • BS2 and BS3 Launch Date in India: The BS2 launch date in India was in 2001, followed by BS3 in 2005. The complete implementation of BS3 standards across the country occurred by the year 2010.
  • BS4 Launch Date in India: India introduced BS4 on April 1 2017. The sale of vehicles under this rule became restricted to BS4-compliant models.
  • When BS6 Started in India: The implementation of BS6 in India began on April 1 2020. 
  • BS3 vs BS6: BS6 vehicles demonstrate greater environmental performance because they produce fewer pollutants through their use of modern emissions control systems compared to BS3 vehicles.

Bharat Stages and their implementation dates

Standard Year Region
India 2000 2000 Nationwide
Bharat Stage II 2001 NCR, Mumbai, Kolkata, Chennai
2005-04 Nationwide
Bharat Stage III 2005-04 NCR
2010-04 Nationwide
Bharat Stage IV 2010-04 NCR
2017-04 Nationwide
Bharat Stage V (Skipped)
Bharat Stage VI 2020-04 Nationwide

Differences in the emission norms

Year CO(g/km) HC(g/km) HC+NOx(g/km) NOx(g/km)
India 2000 2.72–6.90 0.97–1.70
BS2 2.2–5.0 0.5–0.7
BS3 2.3
4.17
5.22
0.20
0.25
0.29
0.15
0.18
0.21
BS4 1.0
1.81
2.27
0.1
0.13
0.16
0.08
0.10
0.11

BS6 emission numbers

Vehicle Class CO (mg/km) HC (mg/km) NOx (mg/km) NMHC (mg/km) PM (mg/km) EVAP (mg/test) Durability

(km)

1 & 2.1 1000 100 60 68 4.5 1500 20000
2.2 1000 100 60 68 4.5 1500 35000
3.1 & 3.2 1000 100 60 68 4.5 1500 35000
CI vehicle 500 100 90 68 4.5

Let us all welcome the new and safer exhaust emission norms and save the environment.

To know all about BS6: BS6 (Bharat Stage 6) | Explained

FAQs

1. Which is best, BS3 or BS4 or BS6?

Bharat Stage 6 engines (BS6) is the best among all 3 as it is helpful in saving the environment. These engines are manufactured and designed in a smart way that produces less pollution in the air. On the other hand, BS3, BS4 engines are banned by the government. 

2. Is BS7 launched in India?

It is assumed that BS7 engines will be launched in 2025-2026 in highly polluted states of India, and from 2027-2028, they will be launched all over the country and play a crucial role in reducing the pollution from vehicles.

3. Is BS4 banned in India?

Yes, there is a ban on registration and sale of BS4 emissions from 1st April 2020. Anyone found to do so is found to be illegal under government laws.

4. What is the difference between BS4 and BS6 emissions?

Bharat Stage 6(BS6) emissions are far better than Bharat Stage 4 engines as they produce 60% less NOx (nitrogen oxides) and 10% less PM (particulate matter) compared to BS4 emissions. It produces 80% nitrogen oxides and 20% particulate matter.

5. When did BS4 start in India?

The BS4 emission standards were enforced across all India on April-1 2017. The sale of these vehicles required BS4 compliance after this date is passed.

6. Is 2017 BS4 or BS6?

The 2017 model vehicle uses BS4 standards for its operation.The 2020 introduction of BS6 standards means that all the 2017 vehicles must comply with these BS4 regulations.

7. Which year car is the BS4?

The BS4 standard applies to which year of vehicles, the time period from 2017 until March 2020 served as- the main time frame when BS4 vehicles became available for distribution in India. The vehicles that received registration during this time frame typically met BS4 standards.

8. Which is the first BS4 car in India?

The first BS4 vehicle to launch in India remains unknown. The majority of vehicle makers updated their complete product lines to meet BS4 requirements before the government deadline of April 2017.

9. When did BS6 come in India?

The BS6 system started its operations in India during the year 2020. The Indian market stopped all BS4 vehicle sales on this date.

Utkarsh Bhardwaj
Utkarsh Bhardwajhttps://gomechanic.in/blog
Technical Content Strategist at GoMechanic | Big Time Petrolhead with the passion for building cars and driving those beauties.

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