After 8 to 12 days, on average, symptoms of measles can begin. The period between measles transmission and the start of symptoms is called the incubation period.
Pennsylvania traffic laws define the maximum speed that any motorist travelling on Pennsylvania roadways can legally drive. Driving over the Pennsylvania speed limit can result in a traffic citation, fine, license suspension, or even arrest. All urban areas have a blanket speed limit of 35mph in Pennsylvania. The speed limit for school zones is 15mph when students are coming to or from school, or whenever the speed limit beacon is flashing. There are a total of 16 states with higher maximum speed limits than Pennsylvania.
To help make school zones safer, the speed limit is 30 km/h in areas where the approaching limit is 50 km/h, when children are present. Where the speed limit is higher than 50 km/h, drivers continue to be required to reduce speed to a maximum of 50 km/h when children are present.