for responders to do so. The driver will then turn on the sirens before proceeding through intersections or when traveling on potentially dangerous stretches of road. Justification for use Anecdotally, the purpose of audible warnings on emergency vehicles is to enable quicker arrival on scene, and to promote safety of crews and spectators. However, rigorous scientific support for this position is very limited. A peer-reviewed study by Hunt et al concluded "the 43.5-second mean time savings does not warrant the use of lights and siren during ambulance transport, except in rare situations or clinical circumstances." In 2017, no scientific studies were found to weigh the benefits of sirens against the costs and hazards of the resulting urban noise. Auxiliary lighting Auxiliary lighting is light used for illumination, to supplement factory-installed headlights or to illuminate areas to the side of or behind the vehicle. It is typically white or near-white light. Some emergency scenes require additional lighting if the emergency workers are to be able to effectively deal with the emergency. Also, building numbers are often obscured by darkness, making it difficult for emergency workers to find the scene of an emergency. For these reasons, emergency vehicles are often equipped with auxiliary lighting, such as: spot-lights, which may be mounted on the side, top, or rear of a larger vehicle, or on the A-post/A-pillar of smaller vehicles. In some states where police vehicles are decommissioned, the department reserves the right to include the spotlight defined as emergency vehicle lighting; in the State of Texas since September 1, 2015 decommissioned police vehicles are sold without the A-pillar spotlight regardless of the lens color (white, or red/blue). Although the vehicle-mounted spot-light is available for purchase e.g. eBay, amazon.com, Craigslist, some states are regulating the sales of certain emergency vehicle equipment as part of a policy mandated by the Department of Homeland Security. flood lights, which may similarly be mounted on the side, top, or rear of a larger vehicle. load lights, which are used by ambulances and other vehicles with cargo doors to light up the area around the cargo doors. alley lights, which are typically found mounted on the side of a police car or emergency vehicle's lightbar, for the purpose of illuminating areas to the side of the car, such as into an alley, or a scene at the side of the road. take-downs, which are typically mounted on the front