PS 103: Human Factors and Safety
Questions and All Correct Answers
2025-2026 Updated.
PS 103 Lesson 1: Understanding the Science of Human Factors
Karen's Error: Karen is a pediatric nurse with more than seven years of experience. She cares for
many sick children: Some cases are simple, others complex. Working in this environment, Karen
and her colleagues experience emotions ranging from joy to pain. It has been a particularly
hectic week for Karen. Not only are three staff nurses out on leave, but the float and per diem
nurses brought in to help have little pediatric experience. Earlier in the week, Karen switched
shifts with another nurse and worked an evening shift and then the following morning shift. On
the final shift for this long week, Karen is on the evening shift again. Karen checks the electrodes
taped to the chest of a four-year-old girl. After pulling up the bed sheet and helping the little girl
get comfortable, she intends to reconnect the lead into the cord from the heart monitor
machine l - Answer The only answer that is probably wrong is inadequate training. There is
no evidence to suggest this. Otherwise, all these factors probably contributed to what
happened. Karen is tired after her busy week, stressed out and distracted by her daughter's
illness, and interrupted by the phone call from her daughter and question from the other nurse.
Ultimately, the design of the equipment allowed her, in her distracted state, to make an error.
PS 103 Lesson 1: Understanding the Science of Human Factors
Your Turn: Remote Control
Here is a quick example of how equipment design can set people up for failure. Look at this TV
remote control:
How do you turn on the TV?
- The small green button at the bottom
- The smaller orange button in the opposite corner
- The large yellow button in the corner - Answer The small green button at the bottom
Most people will quickly reach for the largest button at the top of the remote control. However,
on this remote that button is not the power button. The green button is the power button. If
you had this remote, how many times would you try to turn on the TV and push the wrong
button?
, PS 103 Lesson 1: Understanding the Science of Human Factors
Your Turn: Driving Error
Check your understanding: Which of the following is a skill-based error you might make while
driving?
- You leave work and drive toward home, forgetting you meant to grab something at the store in
the opposite direction.
- While driving to your friend's new home for the first time, you misinterpret directions from
your GPS and take a wrong turn. - Answer The example where you forgot to grab something
is correct.
Driving home from work is something you do all the time, relying on automatic thinking.
Forgetting to drive to the store was a skill-based error.Meanwhile, driving somewhere for the
first time would require more conscious attention and decision-making. In the example, you had
the GPS giving you the information you needed, and you consciously applied the knowledge
incorrectly: a rule-based mistake. (An example of a skill-based error involving GPS would be if
you took a turn you knew you did not want to take because you were following the GPS
instructions without paying attention to what you were doing.)
Your Turn: Two Pilots
In 2008, two pilots on a regional flight fell asleep at the same time and flew the plane 30 miles
past its destination in Hawaii into open ocean. Air traffic controllers tried to contact them nearly
a dozen times during 17 minutes. An investigation found that one pilot's sleep apnea, which
caused him to lose sleep at night and feel fatigue during the day, as well as long work hours,
contributed to the incident.1
Can you identify the internal factors that contributed to the error in this scenario? - Answer -
Illness
- Fatigue
An illness and fatigue (and possibly boredom) were internal factors that contributed to the
error. Long work hours were an external factor, related the individuals' environment, that
contributed to the error.Fatigue is one of the most common physiologic factors that can lead to
error in both automatic and controlled thinking.
Questions and All Correct Answers
2025-2026 Updated.
PS 103 Lesson 1: Understanding the Science of Human Factors
Karen's Error: Karen is a pediatric nurse with more than seven years of experience. She cares for
many sick children: Some cases are simple, others complex. Working in this environment, Karen
and her colleagues experience emotions ranging from joy to pain. It has been a particularly
hectic week for Karen. Not only are three staff nurses out on leave, but the float and per diem
nurses brought in to help have little pediatric experience. Earlier in the week, Karen switched
shifts with another nurse and worked an evening shift and then the following morning shift. On
the final shift for this long week, Karen is on the evening shift again. Karen checks the electrodes
taped to the chest of a four-year-old girl. After pulling up the bed sheet and helping the little girl
get comfortable, she intends to reconnect the lead into the cord from the heart monitor
machine l - Answer The only answer that is probably wrong is inadequate training. There is
no evidence to suggest this. Otherwise, all these factors probably contributed to what
happened. Karen is tired after her busy week, stressed out and distracted by her daughter's
illness, and interrupted by the phone call from her daughter and question from the other nurse.
Ultimately, the design of the equipment allowed her, in her distracted state, to make an error.
PS 103 Lesson 1: Understanding the Science of Human Factors
Your Turn: Remote Control
Here is a quick example of how equipment design can set people up for failure. Look at this TV
remote control:
How do you turn on the TV?
- The small green button at the bottom
- The smaller orange button in the opposite corner
- The large yellow button in the corner - Answer The small green button at the bottom
Most people will quickly reach for the largest button at the top of the remote control. However,
on this remote that button is not the power button. The green button is the power button. If
you had this remote, how many times would you try to turn on the TV and push the wrong
button?
, PS 103 Lesson 1: Understanding the Science of Human Factors
Your Turn: Driving Error
Check your understanding: Which of the following is a skill-based error you might make while
driving?
- You leave work and drive toward home, forgetting you meant to grab something at the store in
the opposite direction.
- While driving to your friend's new home for the first time, you misinterpret directions from
your GPS and take a wrong turn. - Answer The example where you forgot to grab something
is correct.
Driving home from work is something you do all the time, relying on automatic thinking.
Forgetting to drive to the store was a skill-based error.Meanwhile, driving somewhere for the
first time would require more conscious attention and decision-making. In the example, you had
the GPS giving you the information you needed, and you consciously applied the knowledge
incorrectly: a rule-based mistake. (An example of a skill-based error involving GPS would be if
you took a turn you knew you did not want to take because you were following the GPS
instructions without paying attention to what you were doing.)
Your Turn: Two Pilots
In 2008, two pilots on a regional flight fell asleep at the same time and flew the plane 30 miles
past its destination in Hawaii into open ocean. Air traffic controllers tried to contact them nearly
a dozen times during 17 minutes. An investigation found that one pilot's sleep apnea, which
caused him to lose sleep at night and feel fatigue during the day, as well as long work hours,
contributed to the incident.1
Can you identify the internal factors that contributed to the error in this scenario? - Answer -
Illness
- Fatigue
An illness and fatigue (and possibly boredom) were internal factors that contributed to the
error. Long work hours were an external factor, related the individuals' environment, that
contributed to the error.Fatigue is one of the most common physiologic factors that can lead to
error in both automatic and controlled thinking.
