Q1.
In the work represented in the image below, describe how each of the following manifest (if at all):
a. Awkward posture
b. Repetitive motion
c. Forceful exertion
d. Pressure points
e. Static posture
Q2.
Why is it important for employers to put effort into preventing lower back pain and injury?
Q3.
Explain what the advantage is of using signal detection theory to evaluate human thresholds over Fechner's method.
Q4.
On your way home driving your car, you intend to deviate from your normal route in order to get groceries. However, you are also preoccupied with something at work and, when it comes time to turn off of your normal path to the grocery store, you drive past the turn as if you were going home. Based on James Reason's classification of human errors, is this a slip or a mistake? Explain your answer.
Q5.
Find at least two ergonomic issues in the image below. Explain the problems and discuss how they could be addressed.
Q6.
Thigh clearance height, the vertical distance from the top of the thigh to the seat pan, is an important anthropometric measurement in the design of seated work stations: if a worker cannot get close enough to the surface of a work station because their legs simply do not fit under work surface, they are likely to alter their posture, resulting in modified posturing of the back, neck and arms in a reach position, leading to fatigue and possibly strain. For proper seated work station design, it is necessary to specify the minimum thigh clearance between seats and the undersides of work surfaces, controls or other obstacles.
With this understanding, assume you collect these measurements of thigh clearance from your work force to inform the design of a new manufacturing center, or the retrofitting of an existing facility (N = 20; all measurements in millimeters; note that these data represent the data for your entire workforce):
Table I. Thigh clearance height measurements (mm).
|
170
|
192
|
166
|
185
|
|
171
|
164
|
122
|
190
|
|
162
|
188
|
177
|
184
|
|
157
|
155
|
178
|
179
|
|
157
|
157
|
180
|
180
|
a. Calculate the mean and standard deviation for the measurement data in Table I.
b. Based on these statistics, describe how these anthropometric data compare to the US male and Chinese female populations.
c. Calculate the 5th, 50th, 95th, and 99th percentiles for the data in Table I.
d. What percentile would you utilize in the design of a seated work station? Why?
e. If you know that your workforce's stature has mean 1755 mm and standard deviation 70 mm, what would the thigh clearance mean and standard deviation be of a similar population who has a mean stature of 1680 mm with a standard deviation of 55 mm?