All About Bharat Stage Emission Norms

Do you want to know the difference between the BS4 and BS6 and what exact effect BS6 will create for the environment?

Why is there a need for these norms and Why is the government stressing so much on these?

We will discuss everything that will solve your all questions and doubts about Emission norms.

So let’s not waste any time and get started with it- 

WHAT ARE EMISSION NORMS?

The Bharat Stage Emission Standards (BSES) are set by the Central Pollution Control Board under the Ministry of Environment and Climate Change. These emission standards were made mandatory by the Government of India to keep air pollutants under control. Our vehicle engine (Internal combustion engine) emits air pollutants like Carbon monoxide(CO), Hydrocarbons(HC), Nitrogen oxide(NOx), and Particulate matter(PM) which are not good for the environment.

The first Bharat stage (BS) emission norms implemented in 2000, which were based on European (EURO) emission standards then BS2 came in 2005 and BS3 in 20010. However, the emission norms were made more strict only with the enforcement of Bharat Stage IV (BS4). The gap between the first three emission norms was equal and they were introduced at regular intervals. BS4 was introduced in 2017, after a gap of seven years. Thereafter, the Government skipped the implementation of BS5 and introduced BS6 in 2020.

Different types of pollutants – 

• Particulate Matter (PM) – Also known as particle solution and it is a complex mixture of extremely small particles and droplets. The particle size ranges between 2.5 mm diameter (PM_2.5) and 10 mm diameter (PM₁₀). Both particle size is inhalable and can cause serious health problems. The PM is infamous for causing severe lung ailments and has also been found to be carcinogenic (cancer-causing).
• Nitrogen Oxide (NOx) – It is produced from the reaction of nitrogen and oxygen gases in the air during combustion, especially at high temperatures and at a lean air-fuel mixture. NOx gases in vehicle exhaust can cause health problems like lung infection and chronic respiratory problems.
• HydroCarbons (HC) – It is generally referred to as the emissions formed due to unburnt fuel particles. It can cause various health problems like asthma, liver disease, lung disease, and cancer.
• Carbon Oxide(CO) – It is formed when carbon fuels are not burned completely. It can cause headaches, dizziness, vomiting, and nausea.

Changes made with each BS norms – 

• BS1 – Bharat stage 1 came in 2000 and was the same as EURO emission standards and it was known as ‘India 2000’. Maximum permissible Carbon Monoxide(CO) emission of 2.72 g/km, Hydrocarbons (HC)+Nitrogen Oxides(NOx) discharge of 0.97 g/km, and particulate matter release of 0.14.

• BS2 – Bharat stage 2 came in 2005 after 5 years of BS1. Maximum permissible Carbon Monoxide(CO) emission of 2.2 g/km, Hydrocarbons(HC) + Nitrogen Oxides(NOx) release of 0.50 g/km, and suspended particulate matter release of 0.08.  Carmakers accomplished this goal by substituting the carburetor by a Multi-point Fuel Injection (MPFI) system.

• BS3 – Bharat stage3 came in 2010 after 5 years of BS2. Maximum permissible Carbon Monoxide(CO) emission of 2.3 g/km, Hydrocarbons(HC) + Nitrogen Oxides(NOx) release of 0.35 g/km, and suspended particulate matter release of 0.05. The diesel models emitted a peak carbon monoxide(CO) of 0.64 g/km, a nitrous oxide(NOx) of 0.50 g/km, and Hydrocarbons(HC) + Nitrogen Oxides(NOx) release of 0.56 g/km. Besides, the Sulphur content in the BS3 fuels was limited to 100 PPM. Carmakers accomplished this goal by introducing an exhaust system that controlled the release of Carbon Monoxide and Hydrocarbons.

• BS4- Bharat stage4 came in 2010 after 7 years of BS3. Maximum permissible emissions for petrol engines are as follows Carbon Monoxide(CO) emission of 1.0 g/km, Hydrocarbons(HC) + Nitrogen Oxides(NOx)  release of 0.18 g/km, and suspended particulate matter release of 0.025. The diesel models emitted a peak carbon monoxide(CO) of 0.50 g/km, a nitrous oxide(NOx) of 0.25 g/km, and Hydrocarbons(HC) + Nitrogen Oxides(NOx) release of 0.30 g/km. Besides, the Sulphur content in BS4 fuels was confined to 50 PPM. To achieve this goal carmakers added greater exhaust systems to limit nitrogen-based emissions, tuned ECU to guarantee more proficient burning, and modified air intakes.

• BS6- Bharat stage6 came in 2020 after 3 years of BS4. Maximum permissible for petrol vehicles are as follows Carbon Monoxide(CO) emission of 1.0 g/km, Hydrocarbons (HC)+ Nitrogen Oxides(NOx) release of 0.16 g/km, and suspended particulate issue release of 0.05. The diesel models will produce a peak carbon monoxide(CO) of 0.50 g/km, a nitrous oxide(NOx) of 0.06 g/km, and Hydrocarbons(HC) + Nitrogen Oxides(NOx) release of 0.17 g/km. Besides, the Sulphur content in BS6 fuels is confined to 10 PPM. To achieve this goal carmakers are required to add a DPF (DIESEL PARTICULATE FILTER), an SCR (SELECTIVE CATALYTIC REDUCTION) system, and an LNT (LEAN NOX TRAP).

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