In a significant enforcement push to combat Delhi's toxic air, the city's environment minister, Manjinder Singh Sirsa, has revealed that over 10,000 vehicles have failed mandatory emission tests since the implementation of the Graded Response Action Plan (GRAP) Stage-4. Concurrently, authorities have issued more than 2 lakh Pollution Under Control (PUC) certificates.
Enforcement Drive Yields Results, System Upgrades Underway
Minister Sirsa attributed the high compliance rate to the strict "No PUC, No Fuel" rule, which bars vehicles from refueling without a valid certificate. He stated that the 2 lakh tests were conducted after this rule came into effect. The failure of nearly 10,000 vehicles, he emphasized, indicates that enforcement measures are being taken seriously and are producing tangible outcomes.
To streamline the process and enhance reliability, the government is undertaking a major upgrade of all PUC centers. High-capacity equipment is being installed to reduce waiting times and ensure more accurate emission readings. Furthermore, in a move to bolster credibility, a third-party inspection mechanism will be introduced to oversee the certification process, adding a layer of transparency.
Experts Highlight Flaws in Current Testing Regime
Despite the enforcement drive, environmental scientists and researchers point to critical shortcomings in the existing PUC system. The current on-road inspection program is considered weak, relying primarily on simple idle tests for Carbon Monoxide (CO) and Hydrocarbons (HC). For petrol vehicles, a Lambda test is added, while diesel vehicles undergo a smoke density check.
Dr. Rajeev Kumar Mishra, an associate professor at DTU's Department of Environmental Science and Engineering, explained that the current PUC certificate is issued based solely on emissions when the car is idling. He noted that pollutants like NO2, PM2.5, and VOCs (Volatile Organic Compounds), measured at higher engine speeds (fast idle at 2500 rpm), are often recorded but not factored into the certification decision.
Dr. Mishra and other researchers advocate for a more sophisticated approach. They propose that testing and recertification for in-use cars should include fast idle conditions and mass emission testing. Crucially, they argue that a vehicle's fate—whether it should be phased out or granted a PUC—should be determined by its accumulated mileage, maintenance history, and performance against emission norms, not merely its age.
Systemic Issues and the Path Forward
The challenges extend beyond technical parameters to the integrity of the testing centers themselves. Shambhavi Shukla, Programme Manager for Air Pollution at the Centre for Science and Environment (CSE), referenced a 2017 audit by CSE and the EPCA. The audit uncovered alarming malpractices, including certificates being issued without inserting the probe into the tailpipe, centers operating with only a printer and no monitor, and inconsistent results across different facilities.
Shukla emphasized that vehicles remain the second-largest contributor to particulate emissions in Delhi, with exhaust released directly at breathing height posing a severe health risk. While PUC checks help remove the worst polluters from roads, they fail to adequately address harmful emissions like PM2.5. She recommended adopting more advanced surveillance systems, such as remote sensing technology, for better enforcement.
The data presented by the government underscores a vigorous enforcement campaign. However, the consensus among experts is clear: to make a lasting dent in vehicular pollution—a primary source of Delhi's public health crisis—the PUC system requires a fundamental overhaul. This includes integrating mileage-based assessments, expanding the range of pollutants tested, and ensuring rigorous, transparent oversight of certification centers.
