The Government has imposed a ban on construction and demolition activities in the National Capital Region (NCR) as the air quality has deteriorated in the last 24 hours.<br />''<br />''Yesterday, December 30, the city's average air quality index stood at 399, which is only two notches below the severe category.<br />''<br />''The sub-committee of the Commission for Air Quality Management has invoked stage 3 of the Graded Response Action Plan in the Region.  <br />''<br />''Projects related to rail services and operations, metro projects, airport projects, projects related to national security or defence, projects of national importance, and health care facilities are exempted.