When passing on the right is permitted

49-633. When passing on the right is permitted. (1) The driver of a vehicle may overtake and pass upon the right of another vehicle only under the following conditions: (a) When the vehicle overtaken is making or about to make a left turn; (b) Upon a highway with unobstructed pavement of sufficient width for two (2) or more lines of vehicles moving lawfully in the direction being traveled by the overtaking vehicle. (2) The driver of a vehicle may overtake and pass another vehicle upon the right only under conditions permitting such movement in safety. That movement shall not be made by driving off the roadway.