From BS4 to BS6: Key Engine Technology Upgrades You Should Know

The level of air pollution is severely increasing, which is prominent in striking stats like India becoming home to 39 most polluted cities. From the rise in global temperature to the growth in air-borne fatal diseases, many major problems for humans and the planet have arisen from continuous pollution. However, the Indian government has acknowledged that vehicles are emerging as its root cause and the authorities have introduced the shift from BS4 to BS6 engine technologies.

This blog will feature key differences between BS4 and BS6 technologies, which will help you understand why this transition is essential for securing a safer future. Let’s proceed with building a basic understanding of Bharat Stage Emission Standards.

What are Bharat Stage Emission Standards?

BSES are regulations set by the Central Pollution Control Board to control the pollutants released from motor vehicles and other equipment with internal combustion engines. European emission standards or Euro norms, serve as the foundation for BS standards. CPCB introduced the first BS standard 24 years ago, and since then the authority has implemented progressively more stringent norms to control air pollution. However, the latest standard, BS6, made headlines as the country skipped BS-V and directly transformed from BS4 to BS6 four years ago. 

What is Bharat Stage 4 (BS-IV)?

BS-IV standards were implemented by the relevant governing authority in April 2017 to limit the emission of HC+NOX by 23-60% compared to previously introduced BS standards, BS-III. According to this standard, an emission of 50 parts per million sulfur content was permitted. This norm was applicable to all the vehicles manufactured and bought after that date. 

What is Bharat Stage 6 (BS-VI)?

To further minimize the amount of pollutants emitted through a vehicle’s exhaust, the CPCB introduced BS-VI on April 1, 2020. This norm was applicable to all the vehicles manufactured and sold after its implementation date. These standards are stricter and specifically regulate the emission of pollutants like carbon monoxide, methane, nitrogen oxides, etc. Several technological modifications like, On-board diagnostics (OBD) became mandatory for all vehicles after its introduction. This transformation from BS4 engine technology caught the attention of a significant population as it increased the manufacturing and buying rate of vehicles. 

Key Differences Between BS-IV and BS-VI

1. Emission Levels 

The major distinction that was introduced by the implementation of the latest mandated BS standard for vehicles was the amount of pollutants that automobiles are permitted to release into the atmosphere. BS-VI limits nitrogen oxide emissions to 80 mg/km by petrol vehicles, which were allowed up to 250 mg/km during BS-IV. Additionally, the particulate matter emission by both petrol and diesel vehicles was limited to 4.5 mg/km. The change in hydrocarbon made was 170 mg/km.

2. Fuel Type

Another major difference that was introduced by the latest BS-6 engine technology was increasing the quality of fuel required by the vehicles. The BS-VI fuel meets stricter world-standard fuel quality parameters by limiting the harmful emissions of sulfur to 10 ppm from 50 ppm. After the BS-6 norms were mandated, upgrading fuel quality with the advanced sixth version of Euro norms became necessary for vehicle manufacturers. 

3. Technology

To meet stricter BS norms set by the relevant authority, the BS-6 vehicles have been equipped with advanced exhaust gas after-treatment systems. These systems include Selective Catalytic Reduction, which uses a urea-based solution to convert harmful NOx to harmless water vapor and nitrogen; Diesel Particulate Filter, which traps and removes particulate matter from exhaust gases; and Diesel Oxidation Catalysts and Ammonia Slip Catalysts that are after-treatment catalysts. 

4. Mandatory On-board Diagnostics

OBD was not a part of the regulations and standards introduced for BS-IV vehicles. However, the shift from BS4 to BS6 mandates this advanced feature for all vehicles, which alerts the vehicle’s emissions and alerts the driver if there is an issue through real-time monitoring. 

5. Impact on Vehicle Prices

Significant changes like complex engine design, the requirement for better quality fuel, advanced exhaust gas after-treatment systems, and advanced onboard diagnostics are major factors that are resulting in more expensive BS-VI vehicles. Additionally, the insurance policies for vehicles being manufactured and sold complying with the latest BS standards are also high. 

Conclusion 

Overall, the benefits achieved from BS6 engine technology are significant for the betterment of human health, the environment, and the future of our planet. These latest BS standards by the government assist in meeting the need for better air quality by improving combustion, reducing fuel consumption, and limiting emissions. 

Apart from the positive impact on future emissions and the environment, the shift from BS4 to BS6 has ensured a longer lifespan of engine components by increasing their durability against higher temperatures and pressures. BS-VI vehicles are equipped with refined engine components that reduce wear and tear and guarantee a smoother ride with increased power and torque. 

Adapt and adhere to these stringent emission norms of the sixth version of BS standards and contribute towards a greener future with clean air. 

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