It’s 6 a.m. and your cell phone rings. It’s the chief of police and he’s called to notify you that one of the largest factories in your community suffered an explosion and has gone up in flames. Emergency responders are on the scene, but are calling for an immediate evacuation of a multi-block area because toxic chemicals at the plant may cause a deadly cloud of smoke over nearby neighborhoods. Seconds count in a situation like this. How do you notify your citizens and keep them safe?