AIR defense sirens will sound across the city at noon on September 16, which marks this year’s National Defense Education Day.

The drill will test the city’s siren warning system and help residents to familiarize themselves with the rules of air defense sirens. The city’s two airports — Pudong and Hongqiao — are exempted from the drill.

The sirens will sound in three bursts — from 11:35am to 11:58am, each lasting three minutes.