id
stringlengths
24
24
title
stringclasses
442 values
context
stringlengths
151
3.71k
question
stringlengths
12
270
answers
dict
572eb0d603f9891900756958
Elevator
A elevator of this kind uses a vacuum on top of the cab and a valve on the top of the "shaft" to move the cab upwards and closes the valve in order to keep the cab at the same level. a diaphragm or a piston is used as a "brake" if there's a sudden increase in pressure avove the cab. however, to go down, it opens the va...
What is the shaft made of?
{ "answer_start": [ 534 ], "text": [ "acrilic" ] }
572eb0d603f9891900756959
Elevator
A elevator of this kind uses a vacuum on top of the cab and a valve on the top of the "shaft" to move the cab upwards and closes the valve in order to keep the cab at the same level. a diaphragm or a piston is used as a "brake" if there's a sudden increase in pressure avove the cab. however, to go down, it opens the va...
How much weight is permitted on a low capacity elevator?
{ "answer_start": [ 777 ], "text": [ "up to 525 lbs" ] }
572eb3abdfa6aa1500f8d2d3
Elevator
In the first half of the twentieth century, almost all elevators had no automatic positioning of the floor on which the cab would stop. Some of the older freight elevators were controlled by switches operated by pulling on adjacent ropes. In general, most elevators before WWII were manually controlled by elevator opera...
Until the mid 1900s most elevators lacked what?
{ "answer_start": [ 72 ], "text": [ "automatic positioning of the floor on which the cab would stop" ] }
572eb3abdfa6aa1500f8d2d5
Elevator
In the first half of the twentieth century, almost all elevators had no automatic positioning of the floor on which the cab would stop. Some of the older freight elevators were controlled by switches operated by pulling on adjacent ropes. In general, most elevators before WWII were manually controlled by elevator opera...
How were most elevators built before 1939 powered?
{ "answer_start": [ 303 ], "text": [ "by elevator operators using a rheostat connected to the motor" ] }
572eb3abdfa6aa1500f8d2d4
Elevator
In the first half of the twentieth century, almost all elevators had no automatic positioning of the floor on which the cab would stop. Some of the older freight elevators were controlled by switches operated by pulling on adjacent ropes. In general, most elevators before WWII were manually controlled by elevator opera...
Many earlier built freight elevators were controlled by what?
{ "answer_start": [ 191 ], "text": [ "switches operated by pulling on adjacent ropes" ] }
572eb3abdfa6aa1500f8d2d6
Elevator
In the first half of the twentieth century, almost all elevators had no automatic positioning of the floor on which the cab would stop. Some of the older freight elevators were controlled by switches operated by pulling on adjacent ropes. In general, most elevators before WWII were manually controlled by elevator opera...
A rheostat is the size and shape of what?
{ "answer_start": [ 466 ], "text": [ "a cake" ] }
572eb3abdfa6aa1500f8d2d7
Elevator
In the first half of the twentieth century, almost all elevators had no automatic positioning of the floor on which the cab would stop. Some of the older freight elevators were controlled by switches operated by pulling on adjacent ropes. In general, most elevators before WWII were manually controlled by elevator opera...
Where was the rheostat mounted?
{ "answer_start": [ 491 ], "text": [ "upright or sideways on the cab wall" ] }
572eb759dfa6aa1500f8d2f9
Elevator
The elevator motor was located at the top of the shaft or beside the bottom of the shaft. Pushing the handle forward would cause the cab to rise; backwards would make it sink. The harder the pressure, the faster the elevator would move. The handle also served as a dead man switch: if the operator let go of the handle, ...
Where is the elevator motor found?
{ "answer_start": [ 31 ], "text": [ "at the top of the shaft or beside the bottom of the shaft" ] }
572eb759dfa6aa1500f8d2fa
Elevator
The elevator motor was located at the top of the shaft or beside the bottom of the shaft. Pushing the handle forward would cause the cab to rise; backwards would make it sink. The harder the pressure, the faster the elevator would move. The handle also served as a dead man switch: if the operator let go of the handle, ...
Moving the helve forward causes the cab to do what?
{ "answer_start": [ 137 ], "text": [ "to rise" ] }
572eb759dfa6aa1500f8d2fb
Elevator
The elevator motor was located at the top of the shaft or beside the bottom of the shaft. Pushing the handle forward would cause the cab to rise; backwards would make it sink. The harder the pressure, the faster the elevator would move. The handle also served as a dead man switch: if the operator let go of the handle, ...
The more pressure applied to the handle caused what?
{ "answer_start": [ 201 ], "text": [ "the faster the elevator would move" ] }
572eb759dfa6aa1500f8d2fc
Elevator
The elevator motor was located at the top of the shaft or beside the bottom of the shaft. Pushing the handle forward would cause the cab to rise; backwards would make it sink. The harder the pressure, the faster the elevator would move. The handle also served as a dead man switch: if the operator let go of the handle, ...
Why was the handle considered a "dead man switch"?
{ "answer_start": [ 282 ], "text": [ "if the operator let go of the handle, it would return to its upright position, causing the elevator cab to stop" ] }
572eb759dfa6aa1500f8d2fd
Elevator
The elevator motor was located at the top of the shaft or beside the bottom of the shaft. Pushing the handle forward would cause the cab to rise; backwards would make it sink. The harder the pressure, the faster the elevator would move. The handle also served as a dead man switch: if the operator let go of the handle, ...
Eventually safety locks were used to guarantee what?
{ "answer_start": [ 435 ], "text": [ "that the inner and outer doors were closed before the elevator was allowed to move" ] }
572eb90bcb0c0d14000f14c2
Elevator
Some skyscraper buildings and other types of installation feature a destination operating panel where a passenger registers their floor calls before entering the car. The system lets them know which car to wait for, instead of everyone boarding the next car. In this way, travel time is reduced as the elevator makes few...
What function does a "destination operating panel" feature?
{ "answer_start": [ 102 ], "text": [ "a passenger registers their floor calls before entering the car" ] }
572eb90bcb0c0d14000f14c4
Elevator
Some skyscraper buildings and other types of installation feature a destination operating panel where a passenger registers their floor calls before entering the car. The system lets them know which car to wait for, instead of everyone boarding the next car. In this way, travel time is reduced as the elevator makes few...
What is another benefit of a "destination operating panel"?
{ "answer_start": [ 360 ], "text": [ "the computer distributes adjacent stops to different cars in the bank" ] }
572eb90bcb0c0d14000f14c3
Elevator
Some skyscraper buildings and other types of installation feature a destination operating panel where a passenger registers their floor calls before entering the car. The system lets them know which car to wait for, instead of everyone boarding the next car. In this way, travel time is reduced as the elevator makes few...
What is one benefit of a "destination operating panel"
{ "answer_start": [ 272 ], "text": [ "travel time is reduced as the elevator makes fewer stops for individual passengers" ] }
572eb90bcb0c0d14000f14c5
Elevator
Some skyscraper buildings and other types of installation feature a destination operating panel where a passenger registers their floor calls before entering the car. The system lets them know which car to wait for, instead of everyone boarding the next car. In this way, travel time is reduced as the elevator makes few...
What is the downside to a :destination operating panel"?
{ "answer_start": [ 464 ], "text": [ "passenger waiting times may be longer as they will not necessarily be allocated the next car to depart" ] }
572ebc76cb0c0d14000f14e6
Elevator
However, performance enhancements cannot be generalized as the benefits and limitations of the system are dependent on many factors. One problem is that the system is subject to gaming. Sometimes, one person enters the destination for a large group of people going to the same floor. The dispatching algorithm is usually...
What is one example of a limitation on the system?
{ "answer_start": [ 153 ], "text": [ "the system is subject to gaming" ] }
572ebc76cb0c0d14000f14e7
Elevator
However, performance enhancements cannot be generalized as the benefits and limitations of the system are dependent on many factors. One problem is that the system is subject to gaming. Sometimes, one person enters the destination for a large group of people going to the same floor. The dispatching algorithm is usually...
What is generally unable to support variations in the number of people for a particular destination?
{ "answer_start": [ 284 ], "text": [ "The dispatching algorithm" ] }
572ebc76cb0c0d14000f14e8
Elevator
However, performance enhancements cannot be generalized as the benefits and limitations of the system are dependent on many factors. One problem is that the system is subject to gaming. Sometimes, one person enters the destination for a large group of people going to the same floor. The dispatching algorithm is usually...
For what reason do people repeatedly push the up/down buttons on a panel?
{ "answer_start": [ 550 ], "text": [ "people believe this to be an effective way to hurry elevators" ] }
572ebc76cb0c0d14000f14e9
Elevator
However, performance enhancements cannot be generalized as the benefits and limitations of the system are dependent on many factors. One problem is that the system is subject to gaming. Sometimes, one person enters the destination for a large group of people going to the same floor. The dispatching algorithm is usually...
Why is this a bad practice?
{ "answer_start": [ 622 ], "text": [ "this will make the computer think multiple people are waiting and will allocate empty cars to serve this one person" ] }
572ebdfdc246551400ce45d6
Elevator
To prevent this problem, in one implementation of destination control, every user gets an RFID card to identify himself, so the system knows every user call and can cancel the first call if the passenger decides to travel to another destination to prevent empty calls. The newest invention knows even where people are lo...
What is one way to implement destination control?
{ "answer_start": [ 71 ], "text": [ "every user gets an RFID card to identify himself" ] }
572ebdfdc246551400ce45d7
Elevator
To prevent this problem, in one implementation of destination control, every user gets an RFID card to identify himself, so the system knows every user call and can cancel the first call if the passenger decides to travel to another destination to prevent empty calls. The newest invention knows even where people are lo...
How does this help the system?
{ "answer_start": [ 124 ], "text": [ "the system knows every user call and can cancel the first call if the passenger decides to travel to another destination to prevent empty calls" ] }
572ebdfdc246551400ce45d8
Elevator
To prevent this problem, in one implementation of destination control, every user gets an RFID card to identify himself, so the system knows every user call and can cancel the first call if the passenger decides to travel to another destination to prevent empty calls. The newest invention knows even where people are lo...
Newer systems know where and how many people are at a location for what reasons?
{ "answer_start": [ 387 ], "text": [ "either for the purposes of evacuating the building or for security reasons" ] }
572ec147c246551400ce4610
Elevator
During up-peak mode (also called moderate incoming traffic), elevator cars in a group are recalled to the lobby to provide expeditious service to passengers arriving at the building, most typically in the morning as people arrive for work or at the conclusion of a lunch-time period. Elevators are dispatched one-by-one ...
What is another name for up-peak mode?
{ "answer_start": [ 33 ], "text": [ "moderate incoming traffic" ] }
572ec147c246551400ce4611
Elevator
During up-peak mode (also called moderate incoming traffic), elevator cars in a group are recalled to the lobby to provide expeditious service to passengers arriving at the building, most typically in the morning as people arrive for work or at the conclusion of a lunch-time period. Elevators are dispatched one-by-one ...
Generally, up-peak mode takes place during what times of the day?
{ "answer_start": [ 183 ], "text": [ "most typically in the morning" ] }
572ec147c246551400ce4612
Elevator
During up-peak mode (also called moderate incoming traffic), elevator cars in a group are recalled to the lobby to provide expeditious service to passengers arriving at the building, most typically in the morning as people arrive for work or at the conclusion of a lunch-time period. Elevators are dispatched one-by-one ...
What are the reasons for up-peak mode early in the day?
{ "answer_start": [ 216 ], "text": [ "people arrive for work or at the conclusion of a lunch-time period" ] }
572ec147c246551400ce4613
Elevator
During up-peak mode (also called moderate incoming traffic), elevator cars in a group are recalled to the lobby to provide expeditious service to passengers arriving at the building, most typically in the morning as people arrive for work or at the conclusion of a lunch-time period. Elevators are dispatched one-by-one ...
For what reasons are elevators routed one-by-one?
{ "answer_start": [ 320 ], "text": [ "when they reach a pre-determined passenger load, or when they have had their doors opened for a certain period of time" ] }
572ec147c246551400ce4614
Elevator
During up-peak mode (also called moderate incoming traffic), elevator cars in a group are recalled to the lobby to provide expeditious service to passengers arriving at the building, most typically in the morning as people arrive for work or at the conclusion of a lunch-time period. Elevators are dispatched one-by-one ...
Why is a "this car leaving next" sign used?
{ "answer_start": [ 550 ], "text": [ "to encourage passengers to make maximum use of the available elevator system capacity" ] }
572ec373c246551400ce4632
Elevator
Independent service is a special service mode found on most elevators. It is activated by a key switch either inside the elevator itself or on a centralized control panel in the lobby. When an elevator is placed on independent service, it will no longer respond to hall calls. (In a bank of elevators, traffic is reroute...
How is the special sercice mode enabled?
{ "answer_start": [ 87 ], "text": [ "by a key switch either inside the elevator itself or on a centralized control panel in the lobby" ] }
572ec373c246551400ce4633
Elevator
Independent service is a special service mode found on most elevators. It is activated by a key switch either inside the elevator itself or on a centralized control panel in the lobby. When an elevator is placed on independent service, it will no longer respond to hall calls. (In a bank of elevators, traffic is reroute...
What is the impact on an elevator set to independant service mode?
{ "answer_start": [ 236 ], "text": [ "it will no longer respond to hall calls" ] }
572ec373c246551400ce4634
Elevator
Independent service is a special service mode found on most elevators. It is activated by a key switch either inside the elevator itself or on a centralized control panel in the lobby. When an elevator is placed on independent service, it will no longer respond to hall calls. (In a bank of elevators, traffic is reroute...
At what times is Independant service best utilized?
{ "answer_start": [ 596 ], "text": [ "when transporting large goods or moving groups of people between certain floors" ] }
572ec373c246551400ce4635
Elevator
Independent service is a special service mode found on most elevators. It is activated by a key switch either inside the elevator itself or on a centralized control panel in the lobby. When an elevator is placed on independent service, it will no longer respond to hall calls. (In a bank of elevators, traffic is reroute...
During independant service mode how is a single cab in a hall kept from being used?
{ "answer_start": [ 374 ], "text": [ "the hall buttons are disabled" ] }
572ec66cdfa6aa1500f8d38b
Elevator
Inspection service is designed to provide access to the hoistway and car top for inspection and maintenance purposes by qualified elevator mechanics. It is first activated by a key switch on the car operating panel usually labeled 'Inspection', 'Car Top', 'Access Enable' or 'HWENAB'. When this switch is activated the e...
Who is authorized to provide inspection and/or maintenance of the elevator?
{ "answer_start": [ 120 ], "text": [ "qualified elevator mechanics" ] }
572ec66cdfa6aa1500f8d38c
Elevator
Inspection service is designed to provide access to the hoistway and car top for inspection and maintenance purposes by qualified elevator mechanics. It is first activated by a key switch on the car operating panel usually labeled 'Inspection', 'Car Top', 'Access Enable' or 'HWENAB'. When this switch is activated the e...
What is the purpose of the Inspection service?
{ "answer_start": [ 31 ], "text": [ "to provide access to the hoistway and car top for inspection and maintenance" ] }
572ec66cdfa6aa1500f8d38d
Elevator
Inspection service is designed to provide access to the hoistway and car top for inspection and maintenance purposes by qualified elevator mechanics. It is first activated by a key switch on the car operating panel usually labeled 'Inspection', 'Car Top', 'Access Enable' or 'HWENAB'. When this switch is activated the e...
What action initiates it's activation?
{ "answer_start": [ 175 ], "text": [ "a key switch on the car operating panel usually labeled 'Inspection', 'Car Top', 'Access Enable' or 'HWENAB" ] }
572ec66cdfa6aa1500f8d38e
Elevator
Inspection service is designed to provide access to the hoistway and car top for inspection and maintenance purposes by qualified elevator mechanics. It is first activated by a key switch on the car operating panel usually labeled 'Inspection', 'Car Top', 'Access Enable' or 'HWENAB'. When this switch is activated the e...
WWhat's the first thing to happen when the switch is activated?
{ "answer_start": [ 315 ], "text": [ "the elevator will come to a stop if moving" ] }
572ec66cdfa6aa1500f8d38f
Elevator
Inspection service is designed to provide access to the hoistway and car top for inspection and maintenance purposes by qualified elevator mechanics. It is first activated by a key switch on the car operating panel usually labeled 'Inspection', 'Car Top', 'Access Enable' or 'HWENAB'. When this switch is activated the e...
Once activatated, what is the only way to deactivate it?
{ "answer_start": [ 532 ], "text": [ "The elevator can now only be moved by the corresponding 'Access' key switches" ] }
572ec87ac246551400ce4674
Elevator
Phase one mode is activated by a corresponding smoke sensor or heat sensor in the building. Once an alarm has been activated, the elevator will automatically go into phase one. The elevator will wait an amount of time, then proceed to go into nudging mode to tell everyone the elevator is leaving the floor. Once the ele...
What initiates Phase one mode?
{ "answer_start": [ 31 ], "text": [ "a corresponding smoke sensor or heat sensor in the building" ] }
572ec87ac246551400ce4675
Elevator
Phase one mode is activated by a corresponding smoke sensor or heat sensor in the building. Once an alarm has been activated, the elevator will automatically go into phase one. The elevator will wait an amount of time, then proceed to go into nudging mode to tell everyone the elevator is leaving the floor. Once the ele...
What happens when an elevator goes into Phase one mode?
{ "answer_start": [ 177 ], "text": [ "The elevator will wait an amount of time, then proceed to go into nudging mode to tell everyone the elevator is leaving the floor" ] }
572ec87ac246551400ce4676
Elevator
Phase one mode is activated by a corresponding smoke sensor or heat sensor in the building. Once an alarm has been activated, the elevator will automatically go into phase one. The elevator will wait an amount of time, then proceed to go into nudging mode to tell everyone the elevator is leaving the floor. Once the ele...
Where does the elevator go from there?
{ "answer_start": [ 388 ], "text": [ "the elevator will go to the fire-recall floor" ] }
572ec87ac246551400ce4678
Elevator
Phase one mode is activated by a corresponding smoke sensor or heat sensor in the building. Once an alarm has been activated, the elevator will automatically go into phase one. The elevator will wait an amount of time, then proceed to go into nudging mode to tell everyone the elevator is leaving the floor. Once the ele...
How is the elevator enabled for service after the incident?
{ "answer_start": [ 899 ], "text": [ "The only way to return the elevator to normal service is to switch it to bypass after the alarms have reset" ] }
572ec87ac246551400ce4677
Elevator
Phase one mode is activated by a corresponding smoke sensor or heat sensor in the building. Once an alarm has been activated, the elevator will automatically go into phase one. The elevator will wait an amount of time, then proceed to go into nudging mode to tell everyone the elevator is leaving the floor. Once the ele...
What happens if the mode is activated on the fire-recall floor?
{ "answer_start": [ 497 ], "text": [ "the elevator will have an alternate floor to recall to" ] }
572ec9f6c246551400ce4688
Elevator
Phase-two mode can only be activated by a key switch located inside the elevator on the centralized control panel. This mode was created for firefighters so that they may rescue people from a burning building. The phase-two key switch located on the COP has three positions: off, on, and hold. By turning phase two on, t...
How is the Phase-two mode enabled?
{ "answer_start": [ 0 ], "text": [ "Phase-two mode can only be activated by a key switch located inside the elevator on the centralized control panel" ] }
572ec9f6c246551400ce468c
Elevator
Phase-two mode can only be activated by a key switch located inside the elevator on the centralized control panel. This mode was created for firefighters so that they may rescue people from a burning building. The phase-two key switch located on the COP has three positions: off, on, and hold. By turning phase two on, t...
What actions must a firefighter take to activate Phase-two mode?
{ "answer_start": [ 462 ], "text": [ "manually pushes and holds the door close button" ] }
572ec9f6c246551400ce468b
Elevator
Phase-two mode can only be activated by a key switch located inside the elevator on the centralized control panel. This mode was created for firefighters so that they may rescue people from a burning building. The phase-two key switch located on the COP has three positions: off, on, and hold. By turning phase two on, t...
What does Phase-two do?
{ "answer_start": [ 335 ], "text": [ "enables the car to move" ] }
572ec9f6c246551400ce4689
Elevator
Phase-two mode can only be activated by a key switch located inside the elevator on the centralized control panel. This mode was created for firefighters so that they may rescue people from a burning building. The phase-two key switch located on the COP has three positions: off, on, and hold. By turning phase two on, t...
What is the purpose of the Phase-two mode?
{ "answer_start": [ 115 ], "text": [ "This mode was created for firefighters so that they may rescue people from a burning building" ] }
572ec9f6c246551400ce468a
Elevator
Phase-two mode can only be activated by a key switch located inside the elevator on the centralized control panel. This mode was created for firefighters so that they may rescue people from a burning building. The phase-two key switch located on the COP has three positions: off, on, and hold. By turning phase two on, t...
Where is the Phase-two key switch to be found?
{ "answer_start": [ 243 ], "text": [ "on the COP" ] }
572ecdd5cb0c0d14000f15a2
Elevator
Once the elevator arrives at the floor, it will park with its doors open and the car buttons will be disabled to prevent a passenger from taking control of the elevator. Medical personnel must then activate the code-blue key switch inside the car, select their floor and close the doors with the door close button. The e...
Upon arriving at the desinated floor, what does the elevator do?
{ "answer_start": [ 40 ], "text": [ "it will park with its doors open and the car buttons will be disabled to prevent a passenger from taking control of the elevator" ] }
572ecdd5cb0c0d14000f15a3
Elevator
Once the elevator arrives at the floor, it will park with its doors open and the car buttons will be disabled to prevent a passenger from taking control of the elevator. Medical personnel must then activate the code-blue key switch inside the car, select their floor and close the doors with the door close button. The e...
What steps do medical personnel take at that point?
{ "answer_start": [ 170 ], "text": [ "Medical personnel must then activate the code-blue key switch inside the car, select their floor and close the doors with the door close button" ] }
572ecdd5cb0c0d14000f15a4
Elevator
Once the elevator arrives at the floor, it will park with its doors open and the car buttons will be disabled to prevent a passenger from taking control of the elevator. Medical personnel must then activate the code-blue key switch inside the car, select their floor and close the doors with the door close button. The e...
Where then does the elevator go?
{ "answer_start": [ 315 ], "text": [ "The elevator will then travel non-stop to the selected floor" ] }
572ecdd5cb0c0d14000f15a5
Elevator
Once the elevator arrives at the floor, it will park with its doors open and the car buttons will be disabled to prevent a passenger from taking control of the elevator. Medical personnel must then activate the code-blue key switch inside the car, select their floor and close the doors with the door close button. The e...
Once it arrives what does the elevator do
{ "answer_start": [ 381 ], "text": [ "will remain in code-blue service until switched off in the car" ] }
572ecdd5cb0c0d14000f15a6
Elevator
Once the elevator arrives at the floor, it will park with its doors open and the car buttons will be disabled to prevent a passenger from taking control of the elevator. Medical personnel must then activate the code-blue key switch inside the car, select their floor and close the doors with the door close button. The e...
What does the hold feature do?
{ "answer_start": [ 560 ], "text": [ "allows the elevator to remain at a floor locked out of service until code blue is deactivated" ] }
572ed00ac246551400ce46cc
Elevator
When power is lost in a traction elevator system, all elevators will initially come to a halt. One by one, each car in the group will return to the lobby floor, open its doors and shut down. People in the remaining elevators may see an indicator light or hear a voice announcement informing them that the elevator will r...
What sequence of events happens when the power shuts off in a traction elevator and the elevators all stop?
{ "answer_start": [ 95 ], "text": [ "One by one, each car in the group will return to the lobby floor, open its doors and shut down" ] }
572ed00ac246551400ce46cd
Elevator
When power is lost in a traction elevator system, all elevators will initially come to a halt. One by one, each car in the group will return to the lobby floor, open its doors and shut down. People in the remaining elevators may see an indicator light or hear a voice announcement informing them that the elevator will r...
What do any passengers experience at this point?
{ "answer_start": [ 191 ], "text": [ "People in the remaining elevators may see an indicator light or hear a voice announcement informing them that the elevator will return to the lobby shortly" ] }
572ed00ac246551400ce46ce
Elevator
When power is lost in a traction elevator system, all elevators will initially come to a halt. One by one, each car in the group will return to the lobby floor, open its doors and shut down. People in the remaining elevators may see an indicator light or hear a voice announcement informing them that the elevator will r...
After all cars go to the lobby, what is the next step?
{ "answer_start": [ 390 ], "text": [ "the system will then automatically select one or more cars to be used for normal operations and these cars will return to service" ] }
572ed00ac246551400ce46cf
Elevator
When power is lost in a traction elevator system, all elevators will initially come to a halt. One by one, each car in the group will return to the lobby floor, open its doors and shut down. People in the remaining elevators may see an indicator light or hear a voice announcement informing them that the elevator will r...
How are the selected cars then readied for passengers?
{ "answer_start": [ 521 ], "text": [ "The car(s) selected to run under emergency power can be manually overridden by a key or strip switch in the lobby" ] }
572ed00ac246551400ce46d0
Elevator
When power is lost in a traction elevator system, all elevators will initially come to a halt. One by one, each car in the group will return to the lobby floor, open its doors and shut down. People in the remaining elevators may see an indicator light or hear a voice announcement informing them that the elevator will r...
What is a safety feature to prevent entrapment?
{ "answer_start": [ 673 ], "text": [ "when the system detects that it is running low on power, it will bring the running cars to the lobby or nearest floor, open the doors and shut down" ] }
572ed1e0dfa6aa1500f8d409
Elevator
In hydraulic elevator systems, emergency power will lower the elevators to the lowest landing and open the doors to allow passengers to exit. The doors then close after an adjustable time period and the car remains unusable until reset, usually by cycling the elevator main power switch. Typically, due to the high curre...
How do hydraulic elevators work in emergencies?
{ "answer_start": [ 31 ], "text": [ "emergency power will lower the elevators to the lowest landing and open the doors to allow passengers to exit" ] }
572ed1e0dfa6aa1500f8d40a
Elevator
In hydraulic elevator systems, emergency power will lower the elevators to the lowest landing and open the doors to allow passengers to exit. The doors then close after an adjustable time period and the car remains unusable until reset, usually by cycling the elevator main power switch. Typically, due to the high curre...
Once the passengers have exited, what happens?
{ "answer_start": [ 142 ], "text": [ "The doors then close after an adjustable time period and the car remains unusable until reset, usually by cycling the elevator main power switch" ] }
572ed1e0dfa6aa1500f8d40b
Elevator
In hydraulic elevator systems, emergency power will lower the elevators to the lowest landing and open the doors to allow passengers to exit. The doors then close after an adjustable time period and the car remains unusable until reset, usually by cycling the elevator main power switch. Typically, due to the high curre...
For what reason are hydraulic elevators not powered by the standard emergency system?
{ "answer_start": [ 299 ], "text": [ "due to the high current draw when starting the pump motor" ] }
572ed1e0dfa6aa1500f8d40c
Elevator
In hydraulic elevator systems, emergency power will lower the elevators to the lowest landing and open the doors to allow passengers to exit. The doors then close after an adjustable time period and the car remains unusable until reset, usually by cycling the elevator main power switch. Typically, due to the high curre...
What are current-limiting motor starters referred to as?
{ "answer_start": [ 621 ], "text": [ "\"soft-start\" contactors" ] }
572ed638dfa6aa1500f8d42f
Elevator
Statistically speaking, cable-borne elevators are extremely safe. Their safety record is unsurpassed by any other vehicle system. In 1998, it was estimated that approximately eight millionths of one percent (1 in 12 million) of elevator rides result in an anomaly, and the vast majority of these were minor things such a...
What types of elevator hold the highest safety record?
{ "answer_start": [ 24 ], "text": [ "cable-borne elevators" ] }
572ed638dfa6aa1500f8d430
Elevator
Statistically speaking, cable-borne elevators are extremely safe. Their safety record is unsurpassed by any other vehicle system. In 1998, it was estimated that approximately eight millionths of one percent (1 in 12 million) of elevator rides result in an anomaly, and the vast majority of these were minor things such a...
In the late nineties, what was considered the rate of cable-borne elevator problems?
{ "answer_start": [ 175 ], "text": [ "eight millionths of one percent (1 in 12 million) of elevator rides" ] }
572ed638dfa6aa1500f8d431
Elevator
Statistically speaking, cable-borne elevators are extremely safe. Their safety record is unsurpassed by any other vehicle system. In 1998, it was estimated that approximately eight millionths of one percent (1 in 12 million) of elevator rides result in an anomaly, and the vast majority of these were minor things such a...
What was the severity of the majority of elevator failures recorded?
{ "answer_start": [ 301 ], "text": [ "minor things such as the doors failing to open" ] }
572ed638dfa6aa1500f8d432
Elevator
Statistically speaking, cable-borne elevators are extremely safe. Their safety record is unsurpassed by any other vehicle system. In 1998, it was estimated that approximately eight millionths of one percent (1 in 12 million) of elevator rides result in an anomaly, and the vast majority of these were minor things such a...
What is an example of a maintenance-related elevator death?
{ "answer_start": [ 452 ], "text": [ "technicians leaning too far into the shaft or getting caught between moving parts" ] }
572ed638dfa6aa1500f8d433
Elevator
Statistically speaking, cable-borne elevators are extremely safe. Their safety record is unsurpassed by any other vehicle system. In 1998, it was estimated that approximately eight millionths of one percent (1 in 12 million) of elevator rides result in an anomaly, and the vast majority of these were minor things such a...
Before the Twin Towers attack in 2001 , what was the only reported freefall accident attributed to a modern cable-borne elevator?
{ "answer_start": [ 860 ], "text": [ "1945 when a B-25 bomber struck the Empire State Building" ] }
572eddd7dfa6aa1500f8d47f
Elevator
Past problems with hydraulic elevators include underground electrolytic destruction of the cylinder and bulkhead, pipe failures, and control failures. Single bulkhead cylinders, typically built prior to a 1972 ASME A17.1 Elevator Safety Code change requiring a second dished bulkhead, were subject to possible catastroph...
Underground electrolytic malfunctions in hydraulic elevators can result in the destruction of what?
{ "answer_start": [ 87 ], "text": [ "the cylinder and bulkhead" ] }
572eddd7dfa6aa1500f8d480
Elevator
Past problems with hydraulic elevators include underground electrolytic destruction of the cylinder and bulkhead, pipe failures, and control failures. Single bulkhead cylinders, typically built prior to a 1972 ASME A17.1 Elevator Safety Code change requiring a second dished bulkhead, were subject to possible catastroph...
What Elevator Safety Code change required a second dished bulkhead?
{ "answer_start": [ 205 ], "text": [ "1972 ASME A17.1" ] }
572eddd7dfa6aa1500f8d481
Elevator
Past problems with hydraulic elevators include underground electrolytic destruction of the cylinder and bulkhead, pipe failures, and control failures. Single bulkhead cylinders, typically built prior to a 1972 ASME A17.1 Elevator Safety Code change requiring a second dished bulkhead, were subject to possible catastroph...
Before the code change was enacted what was the only permitted hydraulic cylinder type?
{ "answer_start": [ 367 ], "text": [ "single-bottom" ] }
572eddd7dfa6aa1500f8d482
Elevator
Past problems with hydraulic elevators include underground electrolytic destruction of the cylinder and bulkhead, pipe failures, and control failures. Single bulkhead cylinders, typically built prior to a 1972 ASME A17.1 Elevator Safety Code change requiring a second dished bulkhead, were subject to possible catastroph...
Once the cylinder is breached, what calamity does the loss of fluid cause?
{ "answer_start": [ 463 ], "text": [ "uncontrolled down movement of the elevator" ] }
572eddd7dfa6aa1500f8d483
Elevator
Past problems with hydraulic elevators include underground electrolytic destruction of the cylinder and bulkhead, pipe failures, and control failures. Single bulkhead cylinders, typically built prior to a 1972 ASME A17.1 Elevator Safety Code change requiring a second dished bulkhead, were subject to possible catastroph...
What testing does the code require?
{ "answer_start": [ 785 ], "text": [ "periodic testing of the pressure capability" ] }
572edff503f9891900756aa9
Elevator
Safety testing of mine shaft elevator rails is routinely undertaken. The method involves destructive testing of a segment of the cable. The ends of the segment are frayed, then set in conical zinc molds. Each end of the segment is then secured in a large, hydraulic stretching machine. The segment is then placed under i...
What part of the mine shaft requires routine testing?
{ "answer_start": [ 29 ], "text": [ "elevator rails" ] }
572edff503f9891900756aab
Elevator
Safety testing of mine shaft elevator rails is routinely undertaken. The method involves destructive testing of a segment of the cable. The ends of the segment are frayed, then set in conical zinc molds. Each end of the segment is then secured in a large, hydraulic stretching machine. The segment is then placed under i...
What is the first step in destructive testing?
{ "answer_start": [ 136 ], "text": [ "The ends of the segment are frayed, then set in conical zinc molds" ] }
572edff503f9891900756aac
Elevator
Safety testing of mine shaft elevator rails is routinely undertaken. The method involves destructive testing of a segment of the cable. The ends of the segment are frayed, then set in conical zinc molds. Each end of the segment is then secured in a large, hydraulic stretching machine. The segment is then placed under i...
Afterwards, what type of machine is the segment secured in?
{ "answer_start": [ 256 ], "text": [ "hydraulic stretching machine" ] }
572edff503f9891900756aaa
Elevator
Safety testing of mine shaft elevator rails is routinely undertaken. The method involves destructive testing of a segment of the cable. The ends of the segment are frayed, then set in conical zinc molds. Each end of the segment is then secured in a large, hydraulic stretching machine. The segment is then placed under i...
What type of testing is done to the an area of the cable?
{ "answer_start": [ 89 ], "text": [ "destructive testing" ] }
572edff503f9891900756aad
Elevator
Safety testing of mine shaft elevator rails is routinely undertaken. The method involves destructive testing of a segment of the cable. The ends of the segment are frayed, then set in conical zinc molds. Each end of the segment is then secured in a large, hydraulic stretching machine. The segment is then placed under i...
What types of information are collected in the process?
{ "answer_start": [ 360 ], "text": [ "Data about elasticity, load, and other factors is compiled" ] }
572ee270c246551400ce4774
Elevator
Passenger elevators capacity is related to the available floor space. Generally passenger elevators are available in capacities from 500 to 2,700 kg (1,000–6,000 lb) in 230 kg (500 lb) increments.[citation needed] Generally passenger elevators in buildings of eight floors or fewer are hydraulic or electric, which can r...
What dictates passenger elevator capacities?
{ "answer_start": [ 43 ], "text": [ "the available floor space" ] }
572ee270c246551400ce4775
Elevator
Passenger elevators capacity is related to the available floor space. Generally passenger elevators are available in capacities from 500 to 2,700 kg (1,000–6,000 lb) in 230 kg (500 lb) increments.[citation needed] Generally passenger elevators in buildings of eight floors or fewer are hydraulic or electric, which can r...
What capacities are passenger elevators availablee in?
{ "answer_start": [ 128 ], "text": [ "from 500 to 2,700 kg (1,000–6,000 lb) in 230 kg (500 lb) increments" ] }
572ee270c246551400ce4776
Elevator
Passenger elevators capacity is related to the available floor space. Generally passenger elevators are available in capacities from 500 to 2,700 kg (1,000–6,000 lb) in 230 kg (500 lb) increments.[citation needed] Generally passenger elevators in buildings of eight floors or fewer are hydraulic or electric, which can r...
What types of passenger elevators are installed in structures of up to eight floors?
{ "answer_start": [ 286 ], "text": [ "hydraulic or electric" ] }
572ee270c246551400ce4777
Elevator
Passenger elevators capacity is related to the available floor space. Generally passenger elevators are available in capacities from 500 to 2,700 kg (1,000–6,000 lb) in 230 kg (500 lb) increments.[citation needed] Generally passenger elevators in buildings of eight floors or fewer are hydraulic or electric, which can r...
Hydraulic elevators can reach speeds up to 1m/s or how many feet per minute?
{ "answer_start": [ 345 ], "text": [ "200" ] }
572ee270c246551400ce4778
Elevator
Passenger elevators capacity is related to the available floor space. Generally passenger elevators are available in capacities from 500 to 2,700 kg (1,000–6,000 lb) in 230 kg (500 lb) increments.[citation needed] Generally passenger elevators in buildings of eight floors or fewer are hydraulic or electric, which can r...
Electric elevators can reach speeds up to 3 m/s or how many feet per minute?
{ "answer_start": [ 512 ], "text": [ "500" ] }
572eea0ddfa6aa1500f8d4d5
Elevator
Sometimes passenger elevators are used as a city transport along with funiculars. For example, there is a 3-station underground public elevator in Yalta, Ukraine, which takes passengers from the top of a hill above the Black Sea on which hotels are perched, to a tunnel located on the beach below. At Casco Viejo station...
Passenger elevators, used in city transport share similarities to what other ascending and descending vehicles counterbalancing each other?
{ "answer_start": [ 70 ], "text": [ "funiculars" ] }
572eea0ddfa6aa1500f8d4d6
Elevator
Sometimes passenger elevators are used as a city transport along with funiculars. For example, there is a 3-station underground public elevator in Yalta, Ukraine, which takes passengers from the top of a hill above the Black Sea on which hotels are perched, to a tunnel located on the beach below. At Casco Viejo station...
What type of public elevator in Yalta, Ukraine, transport passengers from a hill above the Black Sea to a tunnel down on the beach?
{ "answer_start": [ 116 ], "text": [ "underground public elevator" ] }
572eea0ddfa6aa1500f8d4d7
Elevator
Sometimes passenger elevators are used as a city transport along with funiculars. For example, there is a 3-station underground public elevator in Yalta, Ukraine, which takes passengers from the top of a hill above the Black Sea on which hotels are perched, to a tunnel located on the beach below. At Casco Viejo station...
The elevator located at the Casco Viejo station in the Bilbao Metro is also used for what?
{ "answer_start": [ 430 ], "text": [ "city transportation" ] }
572eea0ddfa6aa1500f8d4d8
Elevator
Sometimes passenger elevators are used as a city transport along with funiculars. For example, there is a 3-station underground public elevator in Yalta, Ukraine, which takes passengers from the top of a hill above the Black Sea on which hotels are perched, to a tunnel located on the beach below. At Casco Viejo station...
How is that set up?
{ "answer_start": [ 465 ], "text": [ "ticket barriers are set up in such a way that passengers can pay to reach the elevator from the entrance in the lower city, or vice versa" ] }
572eeb54c246551400ce47a6
Elevator
A freight elevator, or goods lift, is an elevator designed to carry goods, rather than passengers. Freight elevators are generally required to display a written notice in the car that the use by passengers is prohibited (though not necessarily illegal), though certain freight elevators allow dual use through the use of...
What is another name for a freight elevator?
{ "answer_start": [ 23 ], "text": [ "goods lift" ] }
572eeb54c246551400ce47a7
Elevator
A freight elevator, or goods lift, is an elevator designed to carry goods, rather than passengers. Freight elevators are generally required to display a written notice in the car that the use by passengers is prohibited (though not necessarily illegal), though certain freight elevators allow dual use through the use of...
What type of notice is required to be visible in most freight elevators?
{ "answer_start": [ 151 ], "text": [ "a written notice in the car that the use by passengers is prohibited" ] }
572eeb54c246551400ce47a8
Elevator
A freight elevator, or goods lift, is an elevator designed to carry goods, rather than passengers. Freight elevators are generally required to display a written notice in the car that the use by passengers is prohibited (though not necessarily illegal), though certain freight elevators allow dual use through the use of...
Some freight elevators allow transport of both freight and passengers by using what?
{ "answer_start": [ 321 ], "text": [ "an inconspicuous riser" ] }
572eeb54c246551400ce47a9
Elevator
A freight elevator, or goods lift, is an elevator designed to carry goods, rather than passengers. Freight elevators are generally required to display a written notice in the car that the use by passengers is prohibited (though not necessarily illegal), though certain freight elevators allow dual use through the use of...
How do freight elevators differ from passenger elevators?
{ "answer_start": [ 457 ], "text": [ "Freight elevators are typically larger and capable of carrying heavier loads than a passenger elevator" ] }
572eeb54c246551400ce47aa
Elevator
A freight elevator, or goods lift, is an elevator designed to carry goods, rather than passengers. Freight elevators are generally required to display a written notice in the car that the use by passengers is prohibited (though not necessarily illegal), though certain freight elevators allow dual use through the use of...
What type of elevator is better suited for carrying freight?
{ "answer_start": [ 778 ], "text": [ "electric elevators" ] }
572eecab03f9891900756ae3
Elevator
Stage lifts and orchestra lifts are specialized elevators, typically powered by hydraulics, that are used to raise and lower entire sections of a theater stage. For example, Radio City Music Hall has four such elevators: an orchestra lift that covers a large area of the stage, and three smaller lifts near the rear of t...
How are stage lifts powered?
{ "answer_start": [ 77 ], "text": [ "by hydraulics" ] }
572eecab03f9891900756ae4
Elevator
Stage lifts and orchestra lifts are specialized elevators, typically powered by hydraulics, that are used to raise and lower entire sections of a theater stage. For example, Radio City Music Hall has four such elevators: an orchestra lift that covers a large area of the stage, and three smaller lifts near the rear of t...
How many hydraulic elevators are there at Radio City Music Hall?
{ "answer_start": [ 200 ], "text": [ "four" ] }
572eecab03f9891900756ae5
Elevator
Stage lifts and orchestra lifts are specialized elevators, typically powered by hydraulics, that are used to raise and lower entire sections of a theater stage. For example, Radio City Music Hall has four such elevators: an orchestra lift that covers a large area of the stage, and three smaller lifts near the rear of t...
What is an orchestra lift used for?
{ "answer_start": [ 382 ], "text": [ "to raise an entire orchestra, or an entire cast of performers (including live elephants) up to stage level from below" ] }
572eecab03f9891900756ae6
Elevator
Stage lifts and orchestra lifts are specialized elevators, typically powered by hydraulics, that are used to raise and lower entire sections of a theater stage. For example, Radio City Music Hall has four such elevators: an orchestra lift that covers a large area of the stage, and three smaller lifts near the rear of t...
What is on the background of the image which can be used as a scale to represent the size of the mechanism?
{ "answer_start": [ 509 ], "text": [ "a barrel" ] }
572eef64cb0c0d14000f1682
Elevator
A residential elevator is often permitted to be of lower cost and complexity than full commercial elevators. They may have unique design characteristics suited for home furnishings, such as hinged wooden shaft-access doors rather than the typical metal sliding doors of commercial elevators. Construction may be less rob...
What type of elevators are generally less costly than full commercial elevators?
{ "answer_start": [ 2 ], "text": [ "residential" ] }
572eef64cb0c0d14000f1683
Elevator
A residential elevator is often permitted to be of lower cost and complexity than full commercial elevators. They may have unique design characteristics suited for home furnishings, such as hinged wooden shaft-access doors rather than the typical metal sliding doors of commercial elevators. Construction may be less rob...
What type of doors do commercial elevators use?
{ "answer_start": [ 247 ], "text": [ "metal sliding" ] }
572eef64cb0c0d14000f1684
Elevator
A residential elevator is often permitted to be of lower cost and complexity than full commercial elevators. They may have unique design characteristics suited for home furnishings, such as hinged wooden shaft-access doors rather than the typical metal sliding doors of commercial elevators. Construction may be less rob...
What safety mechanisms are still required, despite lower design costs?
{ "answer_start": [ 412 ], "text": [ "locks on shaft access doors, fall arrestors, and emergency phones" ] }
572eef64cb0c0d14000f1685
Elevator
A residential elevator is often permitted to be of lower cost and complexity than full commercial elevators. They may have unique design characteristics suited for home furnishings, such as hinged wooden shaft-access doors rather than the typical metal sliding doors of commercial elevators. Construction may be less rob...
What type of elevator has a hinged wooden shaft-access door?
{ "answer_start": [ 2 ], "text": [ "residential" ] }
572ef20ecb0c0d14000f1694
Elevator
Some types of residential elevators do not use a traditional elevator shaft, machine room, and elevator hoistway. This allows an elevator to be installed where a traditional elevator may not fit, and simplifies installation. The ASME board first approved machine-room-less systems in a revision of the ASME A17.1 in 2007...
What types of elevators occassionaly do not use a traditional elevator shaft, machine room or hoistway?
{ "answer_start": [ 14 ], "text": [ "residential" ] }
572ef20ecb0c0d14000f1696
Elevator
Some types of residential elevators do not use a traditional elevator shaft, machine room, and elevator hoistway. This allows an elevator to be installed where a traditional elevator may not fit, and simplifies installation. The ASME board first approved machine-room-less systems in a revision of the ASME A17.1 in 2007...
In what year were Machine-room-less elevators first allowed?
{ "answer_start": [ 316 ], "text": [ "2007" ] }