section_path: Design/Interior
section_name: Interior
paragraph_text: Interior
  
  The 787-8 is designed to typically seat 234 passengers in a three-class setup, 240 in two-class domestic configuration, and 296 passengers in a high-density economy arrangement. Seat rows can be arranged in four to seven abreast in first or business—e.g., 1–2–1, 2–2–2, or 2–3–2. Eight or nine abreast are options in economy—e.g., 2–4–2 or 3–3–3. Typical seat room ranges from 46 to 61 in (120 to 150 cm) pitch in first, 36 to 39 in (91 to 99 cm) in business, and 32 to 34 in (81 to 86 cm) in economy.
  
  Cabin interior width is approximately 18 feet (550 cm) at armrest level. The Dreamliner's cabin width is 15 inches (38 cm) more than that of the Airbus A330 and A340, 5 inches (13 cm) less than the A350, and 16 in (41 cm) less than the 777. The 787's economy seats can be up to 17.5 in (44.4 cm) wide for nine-abreast seating and up to 19 inches (48 cm) wide for eight-abreast seating arrangements. Most airlines are selecting the nine-abreast (3–3–3) configuration. The 787's nine-abreast seating for economy provides passengers less space, particularly across the hips and shoulders, than any other jet airliner. Some observers recommended passengers avoid flying 787s with nine-abreast seating, although others suggested that the 787 is more comfortable than other airliners.
  
  The 787's cabin windows have dimensions of 10.7 by 18.4 in (27 by 47 cm), and a high eye level so passengers can maintain a view of the horizon. The composite fuselage permits larger windows without the need for structural reinforcement. Instead of plastic window shades, the windows use electrochromism -based smart glass (supplied by PPG Industries) allowing flight attendants and passengers to adjust five levels of sunlight and visibility to their liking, reducing cabin glare while maintaining a view to the outside world, but the most opaque setting still has some transparency. While the lavatory window also uses smart glass, it was given a traditional sunshade.
  
  The 787's cabin features light-emitting diodes (LEDs) as standard equipment, allowing the aircraft to be entirely "bulbless". LED lights have previously been an option on the Boeing 777 and Airbus aircraft fitted with standard fluorescent lights. The system has three-color LEDs plus a white LED. The 787 interior was designed to better accommodate persons with mobility, sensory, and cognitive disabilities. For example, a 56 by 57 in (140 by 140 cm) convertible lavatory includes a movable center wall that allows two separate lavatories to become one large wheelchair-accessible facility.
  
  The 787's internal cabin pressure is the equivalent of 6,000 feet (1,800 m) altitude, resulting in a higher pressure than for the 8,000 feet (2,400 m) altitude of older conventional aircraft. According to Boeing, in a joint study with Oklahoma State University, this significantly improves passenger comfort. Cabin air pressurization is provided by electrically driven compressors, rather than traditional engine-bleed air, thereby eliminating the need to cool heated air before it enters the cabin. The cabin's humidity is programmable based on the number of passengers carried and allows 15% humidity settings instead of the 4% found in previous aircraft. The composite fuselage avoids metal fatigue issues associated with higher cabin pressure and eliminates the risk of corrosion from higher humidity levels. The cabin air-conditioning system improves air quality by removing ozone from outside air and, besides standard HEPA filters, which remove airborne particles, uses a gaseous filtration system to remove odors, irritants, and gaseous contaminants, as well as particulates like viruses, bacteria and allergens.