請依下文回答第 46 題至第 50 題 The elevators are the primary means of vertical transportation in most high-rise buildings and potentially can play
a vital role in the event of an emergency, such as a fire. The dominant practice around the world, however, is to
discourage the use of elevators during a fire. The major reason for this practice is the unpredictability of the condition
of the emergency and the danger of entrapping passengers as well as rescue workers (e.g. firefighters) in the elevator.
To safeguard the use of elevators in a fire emergency, the US National Institute of Standard and Technology
(NIST) is working with the elevator industry to develop new elevators that function during fires. The new elevators are
designed to be used both as a rescue vehicle, carrying firefighters to the site of the blaze, and as a secondary method
(after stairwells) for evacuating building occupants. NIST is investigating software and sensing systems that can adapt
to changing smoke and heat conditions so that the elevators can maintain safe and reliable operation during fire
emergencies. Such changes could also allow elevators to be operated with remote control from the ground floor during
fires, thus freeing urgently needed firefighters from elevator operation duties. NIST is also testing more reliable
elevator-dedicated emergency power systems and waterproof elevator components to be used in the new generation of
elevators.
Besides hardware and software improvements, NIST also incorporates its expertise in virtual reality simulation
into the making of the new elevators. Virtual reality simulations help test scenarios for coordinating firefighting
activities, and for elevator and stairway evacuation. By including elevators into its graphic computer models, NIST will
help fire safety experts identify the most effective operational procedures for specific fire conditions. Furthermore,
NIST fire researchers hope to collaborate on emergency elevator operations standards with colleagues from around the
world. Global standardization should reduce confusion during an emergency, enabling people to take evacuation
actions with confidence.
【題組】47 What does “Such changes” refer to in the second paragraph?
(A) Having elevator-dedicated emergency power systems.
(B) Improving the software and sensing systems.
(C) Installing waterproof elevator components.
(D) Using remote control operations.