The driver of an emergency vehicle that is stopped to respond to an emergency must mark the location by placing three flares or emergency reflective triangles on the roadway if: (1) Visibility is reduced due to: (a) Weather; (b) Terrain; (c) Time of day; (2) Road conditions at the time of the emergency reduce a driver's ability to slow or stop a motor vehicle; or (3) The nature of the emergency requires emergency vehicles to be at the location for an extended period of time. 25 If traffic on the roadway moves in two directions, one of the flares or emergency reflective triangles must be placed at least one hundred feet in the front, one at least one hundred feet to the rear, and one alongside the stopped emergency vehicle. Upon a one-way roadway or divided highway, one of the flares or emergency reflective triangles must be placed at least one hundred feet to the rear, one at least two hundred feet to the rear, and one alongside the stopped emergency vehicle.