Usage By Country:(4) Europe:In most of Europe emergency vehicles use blue lights. However, it is a darker specification blue than used in other parts of the world. Swedish ambulances and fire engines often use white along with the dark "euro" blue to improve visibility during daylight hours. InSpain, the law allows only theCuerpo Nacional de Policía,Guardia Civil, Policía Local and autonomous law-enforcement agencies to use blue lights, so in contrast with convention in Europe, civil defence, ambulances (Ambulancia) and fire engines (Bomberos) have to use yellow/amber lights (the only other color authorized, in contrast to convention in which these color lights are used to denote slow vehicles). However someAutonomous Communitieshave allowed other colors, such as blue, red or white (the latter two of which is used bySAMURin Madrid), which however, would be technically illegal to use throughout Spain. However, also yellow/amber lights are used in wide-load trucks and their accompanying vehicles. InGermany, only emergency and police vehicle may use blue lights. This includes firefighters, rescue services, emergency response vehicles for public utilities and civil defense units. All other kinds of blue lights (e. g. car floor lighting or cab interior lights) are illegal on public roads. This shall ensure that emergency vehicles are easily recognisable. Flashing blue lights and sirens may only be used by authorised vehicles in case of emergency and order all other vehicles to make way, since these vehicles have the absolute right of way. Blue lights alone may be used to secure the site of an accident (or a standing emergency vehicle)