Memorandum by the Boeing Company
Boeing is pleased to submit evidence to the
Science and Technology Committee in support of its inquiry into
the progress made in the aircraft cabin environment since issuing
its Air Travel and Health Report in 2000. This response includes
a discussion of cabin environment features on current Boeing production
aircraft, enhanced cabin environment features on new products,
and ongoing standards and research activities within which Boeing
Boeing is the world's leading aerospace company
and the largest manufacturer of commercial jetliners and military
aircraft, with capabilities in rotorcraft, electronic and defence
systems, missiles, satellites, launch vehicles and advanced information
and communication systems. Our reach extends to customers in 145
countries around the world, and we are the number one US exporter
in terms of sales. Headquartered in Chicago, Illinois, USA, Boeing
employs more than 153,000 people in more than 67 countries.
Boeing has a long standing relationship with
the UK dating back almost 70 years and today the UK remains a
critically important market for the company, as a supplier base
and a source for technology partners. Boeing's annual spend in
the aerospace industry supports thousands of jobs around the UK,
in the process generating intellectual property and facilitating
Boeing sources more from the UK than from any
other country in the world, except the USA. In 2005, the company
bought more than $1 billion of services and materials from around
300 UK suppliers. There are currently more than 600 Boeing UK
employees, in locations from Glasgow to Dorset.
Boeing Commercial Airplanes (BCA) is the world
leader in commercial aviation because of its complete focus on
airplane operators and the passengers they serve. Boeing products
and services deliver superior design, efficiency and support to
airline customers and allow passengers to fly where they want
to go, when they want to go. By working together with supplier
partners from around the world, Boeing has delivered more than
15,000 airplanes to customers worldwide including airlines, leasing
companies, governments and private firms.
Boeing Commercial Airplanes is headquartered
in Renton, Washington, under the leadership of President and Chief
Executive Officer Scott Carson. It is organised into three primary
business units787 Program, Airplane Programs and Commercial
Aviation Servicesas well as providing Airplane Trading
Cabin environment features on current Boeing
production aircraft include:
HEPA filtration for recirculated cabin air is
basic equipment on all Boeing production aircraft. These filters
capture 99.97% of particles 0.3 microns in diameter. For aircraft
application, the most penetrating particle size is in the range
of 0.1 to 0.2 microns. Capture efficiency exceeds 99.97% for particles
larger than 0.3 microns and smaller than 0.1 microns. HEPA filters
are an effective means to prevent the spread of airborne bacteria
or viruses via the air distribution system.
Ozone converters for outside air are basic equipment
on the Boeing 777 and 747-400 Freighter aircraft, and are optional
equipment on the Boeing 737 and 747-400 Passenger aircraft. Ozone
concentrations in the atmosphere vary with altitude, latitude,
and season. Thus, the need for ozone converters is dependent on
the time of year and routes the aircraft will operate.
Since 2000, design improvement packages to reduce
flight deck noise have been implemented on the Boeing 737 and
747-400. Additional improvements were made to the 737 to reduce
aft cabin noise levels.
Total ventilation rate results in an air change
rate of 20-30 times per hour (compared with an air change rate
of 4-10 times per hour in a typical building). The high air change
rate in the cabin facilitates rapid removal of airborne particulate
Personal air outlets (PAOs) are basic equipment
on the Boeing 737, and are optional equipment on the 747 and 777
aircraft. PAOs provide an effective means for passengers to control
their personal environment.
Boeing has worked, and continues to work, with
leading university and industry researchers to better understand
the multiple factors that influence comfort and health-related
symptoms experienced by passengers and crew in aircraft cabins.
We are dedicated to expanding our knowledge, as well as improving
our products. We continue to conduct research on cabin environment
multiple factors that affect passenger and crew comfort.
Enhanced cabin environment features on the Boeing
787 will include HEPA filtration for recirculated cabin air and
will remain basic equipment for all new products.
Ozone converters for outside air will be basic
equipment for the Boeing 787, as well as the 747-8 Passenger and
Freighter aircraft. These aircraft will fly polar routes at high
altitudes, thus increasing risk for exposure to high atmospheric
Gaseous air purification system for recirculated
cabin air will be basic equipment on the Boeing 787. This system
removes gaseous contaminants, odors and irritants. Research at
the International Center for Indoor Environment and Energy at
the Technical University of Denmark (DTU) demonstrated that the
use of gaseous filtration results in a reduction of symptoms commonly
reported by passengers and crew. This includes some dryness symptoms
typically associated with low humidity and irritation of the respiratory
The ventilation system controls on the Boeing
787 will allow the outside air ventilation rate to be adjusted
per flight based on passenger loading. This capability reduces
fuel burn, and maintains higher relative humidity in the cabin.
The research conducted at DTU demonstrated that the combination
of increased humidity and gaseous purification provide preferred
cabin air quality.
Maximum cabin pressure altitude will be set
at 6,000 feet on the Boeing 787. Research at the Oklahoma State
University Center for Health Services demonstrated a reduction
in cerebral/respiratory symptoms and muscular discomfort after
three to five hours of exposure to a pressure altitude of 6,000
feet compared with exposure to a pressure altitude of 8,000 feet.
The Boeing 787 will have a no-bleed architecture
for the outside air supply to the cabin. This architecture eliminates
the risk of engine oil decomposition products from being introduced
in the cabin supply air in the rare event of a failed engine compressor
seal. In addition, this architecture improves fuel efficiency,
thus reducing fuel burn and associated engine emissions.
Personal air outlets will be basic equipment
on the Boeing 787. This includes nozzles at passenger seats, at
attendant workstations in the galleys, and at attendant seats.
The Boeing 787 will feature an advanced flight
control system. The system can detect and react to vertical gusts
associated with light and moderate turbulence. The reduction in
vertical aircraft displacement will reduce the number of occupants
who experience motion sickness.
Boeing has set aggressive cabin noise level
targets for the 787. Targeted noise levels are less than existing
Boeing continues to support and is actively
engaged in standards and research activities, including the following:
American Society of Heating, Refrigeration and
Air Conditioning Engineers (ASHRAE) Standard 161P for Air Quality
within Commercial Aircraft.
ASHRAE Research Project 1262. This project includes
cabin environmental measurements, and collection of passenger
and crew subjective responses, on over 160 commercial airline
flights. The research will examine the link between aircraft cabin
air and other factors to comfort and health related symptoms experienced
by passengers and crew members.
Federal Aviation Administration (FAA), Center
of Excellence (COE), Aircraft Cabin Environment Research (ACER)
Team. Established in 2004, the FAA COE ACER Team
is engaged in the several research activities, including:
impacts of ozone in passenger
exposure and risks of pesticides
in aircraft cabins;
impacts of reduced pressure
in aircraft cabins;
bleed air contamination incidents;
development of CFD tools to
simulate contaminant transport in aircraft cabins;
evaluation of environmental
air quality (EAQ) and chemical/biological sensors; and
evaluation of technologies for
In summary, the Boeing Company is committed
to providing a safe, healthy and comfortable cabin environment
for passengers and airline crews.
Boeing is committed to maintaining high standards
in the provision of cabin environment features on all its commercial
airliners. Boeing is also constantly developing new ways of improving
the cabin environment and enhancing the passenger experiences.
Many innovative features aimed at improving the cabin environment
can be seen on the Boeing 787, such as increased cabin humidity,
higher cabin pressure and gaseous air purification systems.
18 June 2007
57 Reference: P Strom-Tejsen, et al "Effects
of Gas Phase Adsorption Air Purification on Passengers and Cabin
Crew in Simulated 11-hour Flights", Proceedings of Healthy
Buildings 2006. Back
Technical paper due for publication in June 2007. Back