Quick Answer

CPCB-IV+ (Central Pollution Control Board Stage IV Plus) emission norms have been mandatory for all new diesel generators from 19 kW to 800 kW (approximately 25–1000 kVA) since July 1, 2023. The norms achieve approximately a 90% reduction in particulate matter (PM) and NOx compared to the previous CPCB-II standards. Non-compliant generators cannot be manufactured, sold, or imported in India.

If you're buying a new diesel generator in 2026, it must be CPCB-IV+ compliant. Here's everything you need to know.

What Are CPCB-IV+ Emission Norms?

CPCB-IV+ norms regulate four key pollutants in diesel generator exhaust:

NOx (Oxides of Nitrogen) — causes smog and respiratory disease
PM (Particulate Matter) — fine soot particles harmful to lungs
CO (Carbon Monoxide) — poisonous gas
HC (Hydrocarbons) — contributes to ground-level ozone

The norms were notified via GSR 804(E) dated November 3, 2022 by the Ministry of Environment, Forest and Climate Change (MoEFCC) under the Environment (Protection) Act, 1986.

India leapfrogged from CPCB-II directly to CPCB-IV+, skipping intermediate stages III and IV — mirroring the country's approach with BS-IV to BS-VI vehicle emission norms.

CPCB-IV+ Emission Limits by Engine Power

Engine Power Range	CO (g/kWh)	HC + NOx (g/kWh)	PM (g/kWh)
0–8 kW	5.0	7.5	0.40
8–19 kW	5.0	4.7	0.30
19–37 kW	5.0	4.7	0.30
37–56 kW	5.0	4.7	0.25
56–75 kW	5.0	4.7	0.25
75–130 kW	3.5	4.0	0.20
130–560 kW	3.5	4.0	0.20
Above 560 kW	3.5	4.0	0.20

Which Generators Are Covered?

Applicable to: All gensets with engine power from 19 kW to 800 kW (approximately 25–1000 kVA at 0.8 power factor)
Covers: Both portable and stationary generators, all fuel types
Below 19 kW: Separate, less stringent limits apply
Above 800 kW: Covered under earlier 2002 emission standards

Important: There is no "backup power" exemption. The norms apply to all new gensets regardless of application — prime power, standby, or emergency backup.

What Technology Makes a Generator CPCB-IV+ Compliant?

Electronic Fuel Injection (EFI) — replaces mechanical fuel pumps for precise fuel metering
Exhaust Gas Recirculation (EGR) — recirculates exhaust to reduce NOx formation
Diesel Oxidation Catalyst (DOC) — oxidises CO and HC in the exhaust
Diesel Particulate Filter (DPF) — traps soot particles (PM reduction)
Selective Catalytic Reduction (SCR) — uses urea/AdBlue to reduce NOx (on larger sets)
ECU-controlled engine management — electronic brain managing all emission systems

Penalties for Non-Compliance

First offence: Imprisonment up to 5 years, or fine up to ₹1 lakh, or both
Continuing violation: Additional fine up to ₹5,000 per day
Beyond 1 year: Imprisonment up to 7 years if violation continues
Manufacturers: CPCB can revoke type-approval certificates and ban sale of non-compliant gensets

Frequently Asked Questions

Can I still buy a CPCB-II generator?

No. Since July 1, 2023, manufacturing and sale of non-CPCB-IV+ generators in the 19–800 kW range is banned in India.

Are CPCB-IV+ generators more expensive?

Yes, typically 15–25% more than equivalent CPCB-II models due to advanced emission control technology.

Does CPCB-IV+ apply to gas generators?

CPCB-IV+ primarily targets diesel generators. Dual-fuel generators must comply when operating in diesel-only mode.

Rishabh's CPCB-IV+ Product Range

All Rishabh Power Solutions generators manufactured from 2023 onwards are fully CPCB-IV+ compliant. Browse our range or request a quote.

Sources

CPCB genset notifications (GSR 804(E), Nov 3, 2022) — cpcb.nic.in/genset-notifications/
DieselNet, India Generator Sets Emission Standards
PIB, Regulated Operations of DG Sets in NCR

CPCB-IV+ Compliance for Diesel Generators: What Every Buyer Must Know in 2026