Sixty-four trains travelling to Delhi were delayed, 14 rescheduled, and two cancelled because of the smog.
There were no reports of any planes being delayed.
Air quality meanwhile was recorded as "hazardous" at a number of places.
As was the case in neighbouring Gurgaon and Faridabad.
Air quality in Delhi dips each year as winter approaches, with the cooler air trapping pollutants closer to the ground.
The phenomenon is called "inversion".