Most Polluting Vehicles in Hyderabad-R.T.C Buses

Most Polluting causing Vehicles in Hyderabad-R.T.C Buses
Most Polluting vehicles in Hyderabad are government run Andhra Pradesh Road Transport Corporation.
These emit such a smoke causing most Discomfort to the bikers behind the bus and sometimes even causing suffocation and Irritation to skin, and eyes.
Do these vehicles need to undergo Pollution check and Is Proper maintenance is required or Not.
The survey made by some organisation found that the Centers like Panjagutta has less than 2% oxygen available because of Pollution.
Let us Keep Hyderabad Clean,Green, and Free of Pollution.