Russia announced it will test its emergency warning systems on Oct. 2, with the government telling citizens "don't panic, be calm."At 10:30 a.m. local time, sirens will sound for one minute accompanied by loudspeakers calling "Attention everyone!" and emergency broadcasts on TV and radio.The initiative is a twice-yearly occurrence first introduced in 2020, but which has taken on extra significance since the start of Russia's full-scale invasion.Sirens now sound for real in parts of the country and occupied Ukrainian territories due to Ukrainian drone and missile strikes.Meanwhile in Ukraine, air raid alerts are a daily occurrence in many parts of the country.More than 40,000 air raid sirens lasting from minutes to hours throughout the day and night have sounded across Ukraine since Russia launched its full-scale war over two years ago, according to official reports.In cities heavily-targeted by Russian forces such as Kharkiv, alerts can sound multiple times a day, and last for hours at a timeAt the end of July, Kharkiv broke the record for having the longest air raid siren since the start of the full-scale invasion.It lasted for nearly two days, starting at around 6:31 p.m.