R.I. Gen. Laws § 31-12-8: Warning signals given by emergency vehicles.

The exemptions granted in this chapter to an authorized emergency vehicle shall apply only when the driver of the vehicle while in motion sounds an audible signal by bell, siren, or exhaust whistle as may be reasonably necessary, and when the vehicle is equipped with at least one lighted lamp displaying a red light visible under normal atmospheric conditions from a distance of five hundred feet (500′) to the front of the vehicle, except that an authorized emergency vehicle operated as a police vehicle need not be equipped with or display a red light visible from in front of the vehicle.