(b) If an authorized emergency vehicle displaying any visual signals is parked on the roadside, a sanitation vehicle is performing a task related to the provision of sanitation services on the roadside, a utility service vehicle is performing a task related to the provision of utility services on the roadside, or a wrecker displaying amber rotating or flashing lights is performing a recovery or loading on the roadside, the driver of every other vehicle, as soon as it is safe:1. Shall vacate the lane closest to the emergency vehicle, sanitation vehicle, utility service vehicle, or wrecker when driving on an interstate highway or other highway with two or more lanes traveling in the direction of the emergency vehicle, sanitation vehicle, utility service vehicle, or wrecker, except when otherwise directed by a law enforcement officer. If such movement cannot be safely accomplished, the driver shall reduce speed as provided in subparagraph 2.
2. Shall slow to a speed that is 20 miles per hour less than the posted speed limit when the posted speed limit is 25 miles per hour or greater; or travel at 5 miles per hour when the posted speed limit is 20 miles per hour or less, when driving on a two-lane road, except when otherwise directed by a law enforcement officer.