Bull bars, or grille guards, are metal bars designed to be attached to the front of a vehicle. They serve to protect the vehicle in a collision, especially one with an animal. Regulations have been implemented due to concern for the danger they pose in collisions with pedestrians and other vehicles.
Australia has no federal regulations on bull bars, but states can institute them independently. So far, New South Wales is the only state to do so. Its law prohibits the use of bull bars that are an obvious danger to others on the road. This includes bull bars with protruding corners or sharp edges. It is also illegal to have a bull bar that in any way blocks the driver's view or includes accessories, such as lights or winches, that protrude past the bar itself.
The European Union instated legislation regulating manufacturer production of bull bars. The regulation refers to them by the technical term, frontal protection systems. The EU mandates that all frontal protection systems installed by manufacturers must be tested to ensure their effectiveness in protecting passengers and preventing injury to pedestrians and others. All frontal protection systems must meet government approval. Manufacturers of aftermarket frontal protection systems must also test their systems and provide a list of vehicle models for which they are approved.
There are no federal or state regulations on bull bars in the United States. However, concern is rising. In April 2010 the New York City Council issued a resolution imploring the state legislature to institute a ban on bull bars within New York City limits. It's yet to be seen if this concern for pedestrian safety will have any effect on state or federal vehicle regulations.