A case in point is the Shriram Millennium School, Noida, which has stopped outdoor activities and also tweaked the timings and decided to shut the schoolfor junior classes on Friday.

Utra Singh, principal of Shriram Millennium School, said the environment has become bad in the past few days. "We have banned outdoor activities for our students. We have also shifted the opening time for classes from 8am to 9am. The closing time has also been advanced from 2.30pm to 2pm in the afternoon," she said.

The move came after some parents told the school management about issues with the increasing pollution level in the city. The school students have also written a letter to the prime minister to draw up a plan and address the problem of pollution.

SAFAR (System of air quality and weather forecasting and research), under the ministry of earth science, on Thursday recorded PM10 at 434 and PM2.5 at 500+ which falls under the severe category.

Meanwhile, several other schools have not made any changes in their schedule. An official of Amity International School said the school management has not taken any such decision. "We have not issued any such advisory in this regard," the officials said.

N P Singh, district magistrate, said the administration would talk to some well-known paediatricians and school principals and take their opinion about the school closure. "We will take their suggestions before taking a final decision," Singh said.

The district administration, however, issued an advisory to the developers to ensure compliance to check dust particles mixing with the air, which leads to air pollution. He said the developers should ensure that appropriate protection measures are taken to ensure that no construction material dust flies outside the plot area. The DM has also asked the transport department to conduct a drive against polluting vehicles.