Ind. Code § 9-19-14-2

Sec. 2. Except as provided in section 5 of this chapter, an authorized emergency vehicle must, in addition to other equipment required by this article, be equipped with signal lamps that are capable of displaying flashing, rotating, or oscillating beams of red or red and white light. The lights must be visible to oncoming traffic one hundred eighty (180) degrees around the front of the vehicle.