The total width of exits required is determined by calculating the number of occupants and applying the required exit width per occupant based on the applicable building or fire code (such as NFPA 101, Life Safety Code). For a large assembly occupancy such as a soccer field with 15,500 people, the exit width would be calculated using a standard factor (usually in inches or millimeters per person) to ensure that all occupants can evacuate safely in an emergency. Based on standard exit width factors and the number of people, the correct total exit width required is approximately6,200 inches (157,500 mm).