A
“STEP BY STEP” GUIDE
Answers to Your Building Transportation Questions
Building transportation is equipment
that includes elevators, escalators and moving walks used for the movement of
passengers or goods within a building.
ELEVATORS
What is an elevator?
An elevator is a hoisting or lowering mechanism,
designed to carry passengers or goods (freight), and is equipped with a car and
platform that typically moves in fixed guides and serves two or more landings.
What’s the difference between a traction elevator and
a hydraulic elevator?
Traction elevators have an elevator car and
counterweight attached to opposite ends of hoist ropes. The hoist ropes pass
over a driving machine that raises and lowers the car. Traction elevators run
on load-bearing rails in the elevator hoistway. Traction elevators are most
often used in mid-rise and high-rise buildings with five or more floors.
Hydraulic
elevators, on the other hand, are raised by forcing pressurized oil through a
valve into a steel cylinder located above ground or underground. The pressure
forces a piston to rise, lifting the elevator platform and car enclosure
mounted on it. The car is lowered by opening the valve and allowing the weight
of the car to force oil from the cylinder in a controlled manner. When the
valve is closed the car is stopped. Since the weight of hydraulic elevator cars
is borne by the piston, there is no need for a structural framework or
load-bearing rails. Hydraulic elevators are commonly found in low-rise
buildings with two to five floors.
A roped
hydraulic elevator is a hydraulic elevator where the cylinder is connected to
the car by wire ropes or indirectly coupled to the car by means of wire ropes
and sheaves.
What
is a Machine Room-Less (MRL) elevator?
Machine Room-Less
elevators are those that do not require a machine room. They do not run on
hydraulics and the only space they require is the hoistway. Because of these
features, MRL can help buildings save space and reduce energy requirements.
How
long have elevators been in use?
Since the
19th century, power elevators, often steam-operated, were used for conveying
materials in factories, mines, and warehouses. In 1853, American inventor
Elisha Otis demonstrated a freight elevator equipped with a safety device to
prevent falling in case a supporting rope should break. This increased public
confidence in such devices. In 1846, Sir William Armstrong introduced the
hydraulic crane, and in the early 1870s, hydraulic machines began to replace
the steam-powered elevator. German inventor Werner von Siemens built the first
electric model in 1880.
ESCALATORS
What is an escalator?
How does an escalator work?
An escalator is a
power-driven, continuously moving, inclined stairway. Varying by design and
planned usage, an escalator can rise from 4 feet to over 100 feet and may go
floor-to-floor or skip floors. Escalators transport more than 245 million
people everyday.
Escalators are an endless
chain of moving steps driven by a motor. This motor turns the main drive shaft,
which powers the step chain to move the steps. Balustrades, or the sides of the
escalator, are mounted on either side of the steps and a continuously moving
belt at the top of each balustrade forms the handrail. The escalator’s steps
are actually wedge-shaped units that move along a continuous conveyer.
How long have
escalators been in use?
The first patent for a
“revolving” stair, the escalator’s predecessor, was issued in 1859. Charles
Seeberger and Jesse Reno invented the first escalators as we know them today.
Seeberger trademarked the term escalator and exhibited his product at the Paris
Exhibition in 1890. Jesse Reno installed his “inclined elevator” at the Third Avenue and 59th Street elevated station in New York City about that same time.
MOVING WALKS
What is a moving walk?
Moving walks are designed for use where the
elimination of long walks is desired and in areas where traffic patterns are
constant and heavy, such as airports, exhibition halls and subways. They are
similar to escalators except that the passenger-carrying surface remains
parallel to its direction of motion and is uninterrupted. Moving walks are
sometimes used to move passengers from one floor to another along a gradual
incline.
What is NEII?
The National Elevator Industry, Inc.,
NEII, the national trade association of the building transportation industry, was established to promote safe building transportation for new and existing products and technologies, the adoption of current codes by local government agencies, and to encourage responsible legislation and regulatory measures at all levels of government. Regular membership is available to those corporations, firms or companies that, as part of their normal business operations, provide or perform any of the following: manufacturing (including parts or components used by others in the manufacture, repair or maintenance), installation, or the repair and maintenance of elevators, escalators, moving walks and related equipment. Trust membership is available to those corporations, firms, or companies that, as part of their regular business, employ members of the International Union of Elevator Constructors (IUEC) and contribute to the benefit trusts (Trusts) established by agreements between the IUEC and NEII. Individual memberships are available to persons who are not employees of NEII member companies or organizations. NEII promotes safe building transportation and works with various organizations on the formation, adoption and enforcement of the latest building transportation codes and standards.
NEII is a leader in promoting
safe building transportation for new and existing products and technologies, as
well as working with local government agencies to encourage the enforcement of
the latest codes and standards.
What steps has NEII
taken to improve building transportation safety?
NEII improves
elevator and escalator safety by driving the formulation of codes and standards
that provide for the safety of the riding public and encourage the introduction
of safer technology. The organization also promotes communication and
coordination with governmental agencies regarding adoption and enforcement of
the latest ASME A17 codes and standards.
Although escalator
accidents are rare compared to the millions of passengers who ride them each
day, the escalator industry continuously works to improve safety. NEII has
focused on reducing the potential of step/skirt entrapments. It partnered with Arthur
D. Little, Inc., to develop a Step/Skirt Performance Index that offers a
reliable standard from which all escalators, new and old, can be measured. This
Index was adopted and is now part of the ASME A17.1, the basis for all state
and local escalator codes throughout the United States.
The Index measures the
potential for possible entrapments between the moving stair and the stationary
sidewall. Mounting deflector devices on the skirt significantly reduce the
chance of contact between a child’s calf and the escalator skirt.
Recently,
NEII members helped develop
the Performance Based Safety Code (PBC)
for Elevators and Escalators, or ASME
A17.7/CSA B44.7. The PBC is a companion to the 2007 version of the Safety Code
for Elevators and Escalators, ASME A17.1/CSA B44, and provides Authorities
Having Jurisdiction (AHJs) with an objective and structured method for
approving new technology while ensuring continued elevator
safety.
How many elevators and escalators
are there in North America?
There are approximately one
million elevators and almost 44,000 escalators in North America alone.
Escalators are found everywhere from airports and train stations to shopping
malls, hotels, office buildings and theme/amusement parks.
How many people use
building transportation each day?
There are approximately 325
million elevator passengers and 245 million escalators passengers daily in North America. Excluding automobiles, that is more than the total riders of all other forms
of transportation combined. The average elevator rider takes four trips per
day, 250 days per year.
Do all forms of
building transportation, including elevators and escalators, need to be
maintained?
Yes. Elevators and escalators
are made of millions of moving parts. Like an automobile, which requires
tune-ups, oil changes and periodic replacement of worn out parts, elevators and
escalators must also be tested and inspected for sound working order. Equipment
component life is directly related to the amount of building transportation use
and maintenance, and worn out parts must be replaced.
Who is responsible for
maintaining elevators and escalators?
Building transportation
safety is the responsibility of building owners with the help of elevator and
escalator manufacturers, maintenance companies, and passengers. Building owners
and managers must ensure that their elevators and escalators are maintained,
meet all code requirements and are inspected and tested as required by local
codes. Many elevator and escalator companies have tools that can help building
managers asses their maintenance needs.
Is the building
transportation industry regulated?
The American Society of Mechanical Engineers (ASME)
sets stringent standards that form the basis for all elevator, escalator and
moving walk codes in North America, which must be followed by building
transportation manufacturers, building owners and managers, and maintenance
companies. The ASME A17.1/CSA B44 Safety Code for Elevators and Escalators
recommends that all forms of building transportation be inspected and tested
annually, and in some instances every six months, for compliance with the code.
The local jurisdiction is required by the ASME A17.1/CSA B44 Code to establish
the inspection and testing frequency for that jurisdiction. The ASME A17.1/CSA B44 Code is the code used by every AHJ in the U.S. and Canada that regulates elevators,
escalators and moving walks.
What are the most common
types of building transportation accidents?
Slips, trips and falls by the
elderly are the most common types of accidents that occur on escalators, and
most are due to unsafe riding practices. The neglect of safety rules among
children is another significant cause of accidents. Trips, falls and being
struck by closing doors when entering and exiting elevators are the most
prevalent accidents that occur on elevators. Most of these incidents are due to
being inattentive to one’s surroundings. All riders need to be careful when
using building transportation and follow certain rules to ensure safety.
Building owners and managers can help educate passengers about how to safely
ride elevators, escalators and moving walks by posting simple safety tips.
For more
information on vertical transportation safety, please go to the NEII Safety
pages for elevators and escalators.
CONTACT: NEII Media Relations
