There are two main types of smoke alarm tech, says Raman Chagger, principal consultant at BRE, the Building Research Establishment. Ionisation-based systems use a tiny amount of radioactive material to charge, or ionise, particles in the air which flow between two small plates. Should smoke interrupt that flow of charged particles, the alarm goes off.
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These orchestrated demonstrations climaxed on Aug. 19, 1953, when pro-shah forces and sympathetic leaders in the Iranian military – with CIA financial and logistical backing – seized key points of the country, confronted Mossadegh loyalists and helped topple his government. Estimates suggest around 200 to 300 people were killed in the chaotic fighting in Tehran.
A big week ahead. It all starts Monday morning! #AppleLaunch pic.twitter.com/PQ9gM2Gl2r