instruction: Based on this article, what countries have implemented the use of a dead man zone?
context: Outcomes from Project Vesta have been integrated into firefighter training in Australia and are beginning to appear in the United States.
  
  Firefighters try to stay out of the dead man zone at all times, working from safe points such as burnt ground or a large area of non-burnable ground, such as a cricket or Australian rules football oval, or a large car park. This is achieved by attacking the fire from the flanks, or the rear, so that burnt ground is always nearby, and the fire is always in front of the firefighters. This avoids two disadvantages of attacking fires at the head of the fire where spot fires may start behind them or changes in wind behavior might accelerate the spread of the fire.
  
  The result of several inquiries into firefighter death in Australian bushfires found that firefighters should stay out of the dead man zone and that they should always keep 250 liters of water in their truck for personal safety. This is now a standard operating procedure in the NSW Rural Fire Service, Country Fire Service and Country Fire Authority in Australia.
response: Australia and the United States have used the dead man zone from Project Vesta