Vehicle Safety Lights

Minnesota DOT has a warning light standard for its fleet and for contractor vehicles inside workzones:
MnDOT will only recognize LED lights that meet the California Title 13 standards and MUST be on this list. This list is updated yearly. Non-LED vehicle warning lights used in MnDOT work zones must comply with SAE specifications J1318 or J845 as a Class 1 or 2 device using a yellow or amber lens. Regardless of model, colors other than amber or yellow or coverage zones less than 360 degrees are not authorized for this list, even though the light may bear a model number similar to one below. The manufacturers below claim the following models comply with the above SAE specification. Manufacturers may apply the same name to various lights. In all cases, ensure the particular model conforms to SAE specifications as a Class 1 or 2 device.