Vaisala's January - March (Q1/2011) results published on May 6, 2011

29 april 2011 Vaisala Stock Exchange Release 29.04.2011 at 3:15 p.m. Vaisala publishes its Q1/2011 results on Friday, May 6, 2011 at 9:00 a.m. The stock exchange release will be available on the company website atwww.vaisala.com. CEO's presentation will be published at 12.00 noon (GMT +2) on the same day at www.vaisala.com/investors. Briefing Briefing for analysts and media will be arranged in Tapahtumatalo Bank, Meeting Point 2nd fl, Unioninkatu 20, Helsinki, starting at 12.00 a.m. Please register to the briefing by email toliisa.ahtiluoto@vaisala.com. Audiocast A live audiocast of the presentation of Kjell Forsén, President and CEO of Vaisala, will be sent starting at 12.00 a.m. (GMT +2). The audiocast will be available atwww.vaisala.com/investors. It will be recorded and published at the same address at 2.00 p.m. (GMT +2) on the same day. More information: Liisa Ahtiluoto, Communications Manager, tel. +358 40 730 7695 --------------- Vaisala is a global leader in environmental and industrial measurement. Building on 75 years of experience, Vaisala contributes to a better quality of life by providing a comprehensive range of innovative observation and measurement products and services for meteorology, weather critical operations and controlled environments. Headquartered in Finland, Vaisala employs over 1300 professionals worldwide and is listed on the NASDAQ OMX Helsinki stock exchange. www.vaisala.com This announcement is distributed by Thomson Reuters on behalf of Thomson Reuters clients. The owner of this announcement warrants that: (i) the releases contained herein are protected by copyright and other applicable laws; and (ii) they are solely responsible for the content, accuracy and originality of the information contained therein. Source: Vaisala Oyj via Thomson Reuters ONE [HUG#1510823]