India amends emission standards for agricultural tractor, power tiller and combine harvester, etc. 
On October 5, 2020, India’s Ministry of Road Transport and Highways published the “Central Motor Vehicles (Thirteenth Amendment) Rules, 2020” to amend the emission standards for agricultural tractor, power tiller and combine harvester, etc. A summary of the amendments is as follows.
Every agricultural tractor, power tiller and combine harvester shall be so manufactured that it complies with the following standards of gaseous pollutants emitted by them when tested on following duty cycle.
- for variable-speed engines, the 8-mode test cycle or the corresponding ramped modal cycle and the transient cycle Non Road Transient Cycle (NRTC)
- for constant-speed engines, the 5-mode test cycle or the corresponding ramped modal cycle
- emissions (g/kWh) shall be measured over applicable emission limit for Non-Road Safety Cycle (NRSC) and Non-Road Transient Cycle (NRTC) test cycle as per test applicability mentioned in Table 1 and Table 2 given below and for NRTC test cycle, composite weighted emissions shall be computed by weighing the cold start results 10% and the hot start results 90%. Weighted composite results shall meet the limits given in said tables
Table 1 (TREM Stage – IV)
Applicable emission limit for Non-Road Steady Cycle (NRSC) and Non-Road Transient Cycle (NRTC) test cycle
| Category, kW | Applicable with
effect from |
CO | HC | NOx | PM | Test Cycle |
| g/kWh | ||||||
| 37 ≤P < 56 | October 1, 2021 | 5.0 | 4.7（HC+NOx） | 0.025 | NRSC and NRTC | |
| 56 ≤P < 130 | 5.0 | 0.19 | 0.4 | 0.025 | ||
| 130≤P < 560 | 3.5 | 0.19 | 0.4 | 0.025 | ||
※Test cycle as described in AIS: 137and as amended from time to time.
Table 2 (TREM Stage –V)
Applicable emission limit for Non-Road Steady Cycle (NRSC) and Non-Road Transient Cycle (NRTC) test cycle
| Category, kW | Applicable with
effect from |
CO | HC | NOx | PM | PN | Test Cycle |
| g/kWh | #/kWh | ||||||
| P < 8 | April 1, 2024 | 8.0 | 7.5（HC+NOx） | 0.4 | ― | NRSC | |
| 8 ≤P < 19 | 6.6 | 7.5（HC+NOx） | 0.4 | ― | |||
| 19 ≤P < 37 | 5.0 | 4.7（HC+NOx） | 0.015 | 1×1012 | NRSC and NRTC | ||
| 37 ≤P < 56 | 5.0 | 4.7（HC+NOx） | 0.015 | 1×1012 | |||
| 56 ≤P < 130 | 5.0 | 0.19 | 0.4 | 0.015 | 1×1012 | ||
| 130 ≤P < 560 | 3.5 | 0.19 | 0.4 | 0.015 | 1×1012 | ||
| P ≥ 560 | 3.5 | 0.19 | 3.5 | 0.045 | ― | NRSC | |
The following shall also be complied with in accordance with AIS: 137
Table 3 Tolerance for Gross Power Measurement
| Engine Type | Rated power [%] | Other measurement points on the curve [%] | Tolerance for engine speed [%] |
| Type approval | ±2 | ±4 | ±1.5 |
| Conformity of
production |
±5 | ±10 | ±5 |
Table 4 Engine test for evaluating deterioration factors
| Category ( Power Band) | Emission durability period (hours) |
| ≤ 37 kW （constant speed Engines） | 3000 |
| ≤ 37 kW （Variable speed Engines) | 5000 |
| > 37 kW | 8000 |
Table 5 Multiplicative deterioration factors （alternative）
| Test Cycle | CO | HC | NOx | PM |
| NRSC | 1.3 | 1.3 | 1.15 | 1.05 |
| NRTC | 1.3 | 1.3 | 1.15 | 1.05 |
In addition, it also sets emission standards for construction equipment vehicles.
The amendment rules can be downloaded from the following URL.
