T. Armstrong
U of Michigan
http://www-personal.umich.edu/~tja/
Procedures for determining the normal time needed for a qualified and trainined worker/user to complete a given job/task to given standards using a standard methods under standard condtions
Example 1:How is determining the time required to complete a task analogous to determining the height of a door opening?
Example 2: Text entry: How much time is required to send a 50 character text message using the touch screen and using voice inputs
Table : Comfortable adult (20—79 years) walking speeds (average ± standard deviation, 5th %tile)-- What is normal?
Age | Males | Females |
20-30 | 1.39±0.15, 1.14 | 1.41±0.18, 1.11 |
30-40 | 1.45±0.09, 1.30 | 1.42±0.13, 1.21 |
40-50 | 1.46±0.16, 1.12 | 1.39±0.16, 1.13 |
50-60 | 1.39±0.23, 1.01 | 1.40±0.15, 1.15 |
60-70 | 1.35±0.20, 1.02 | 1.30±0.21, 0.95 |
70-80 | 1.33±0.20, 1.00 | 1.27±0.21, 0.92 |
A designaged sequence of steps for determine the normal time to complete a job/task to specified standards.
The conditions that were observed and considered in the development of the normal time
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n | ti | Δti | Element | Walk Δt1i | Deliver Δt2i | Comment |
---|---|---|---|---|---|---|
1 | 0.44 | 0.44 | walk | 0.44 | ||
2 | 0.55 | 0.11 | deliver | 0.11 | ||
3 | 0.98 | 0.43 | walk | 0.43 | ||
4 | 1.09 | 0.11 | deliver | 0.11 | ||
5 | 1.48 | 0.39 | walk | 0.39 | ||
6 | 1.6 | 0.12 | deliver | 0.12 | ||
7 | 2.14 | 0.54 | walk | 0.54 | ||
8 | 2.89 | 0.75 | deliver | -- | damaged mailbox | |
9 | 3.27 | 0.38 | walk | 0.38 | ||
10 | 3.36 | 0.09 | deliver | 0.09 | ||
11 | 3.73 | 0.37 | walk | 0.37 | ||
12 | 3.83 | 0.1 | deliver | 0.1 | ||
13 | 4.32 | 0.49 | walk | 0.49 | ||
14 | 4.41 | 0.09 | deliver | 0.09 | ||
15 | 4.69 | 0.28 | walk | 0.38 | ||
16 | 4.78 | 0.09 | deliver | 0.09 | ||
17 | 5.2 | 0.42 | walk | 0.42 | ||
18 | 5.32 | 0.12 | deliver | 0.12 | ||
19 | 5.71 | 0.39 | walk | 0.39 | ||
20 | 5.82 | 0.11 | deliver | 0.11 | ||
21 | 6.20 | 0.38 | walk | 0.38 | ||
22 | 6.32 | 0.12 | deliver | 0.12 | ||
23 | 7.02 | 0.7 | walk | 0.47 | ||
24 | 7.12 | 0.1 | deliver | 0.1 | ||
25 | 7.82 | 0.7 | walk | 0.43 | ||
26 | 7.92 | 0.1 | deliver | 0.1 | ||
27 | 13.65 | 5.73 | walk | -- | aggressive dog | |
28 | 13.76 | 0.11 | deliver | 0.11 | ||
29 | 14.11 | 0.35 | walk | 0.35 | ||
30 | 14.2 | 0.09 | deliver | 0.09 | ||
31 | 14.88 | 0.68 | walk | 0.68 | ||
32 | 14.97 | 0.09 | deliver | 0.09 | ||
33 | 15.36 | 0.39 | walk | 0.42 | ||
34 | 15.46 | 0.1 | deliver | 0.1 | ||
35 | 15.9 | 0.44 | walk | 0.44 | ||
36 | 16 | 0.1 | deliver | 0.1 | ||
37 | 16.49 | 0.49 | walk | 0.49 | ||
38 | 16.59 | 0.1 | deliver | 0.1 | ||
39 | 17.06 | 0.47 | walk | 0.47 | ||
40 | 17.16 | 0.1 | deliver | 0.1 | ||
41 | 17.59 | 0.43 | walk | 0.43 | ||
42 | 17.68 | 0.09 | deliver | 0.09 | ||
43 | 18.13 | 0.45 | walk | 0.45 | ||
44 | 21.06 | 2.93 | deliver | -- | stopped for signature | |
45 | 21.48 | 0.42 | walk | 0.42 | ||
46 | 21.57 | 0.09 | deliver | 0.09 | ||
47 | 21.92 | 0.35 | walk | 0.35 | ||
48 | 22.03 | 0.11 | deliver | 0.11 | ||
49 | 22.41 | 0.38 | walk | 0.38 | ||
50 | 22.53 | 0.12 | deliver | 0.12 | ||
51 | 23.04 | 0.51 | walk | 0.51 | ||
52 | 23.15 | 0.11 | deliver | 0.11 | ||
53 | 23.67 | 0.52 | walk | 0.52 | ||
54 | 23.78 | 0.11 | deliver | 0.11 | ||
55 | 24.04 | 0.26 | walk | 0.46 | ||
56 | 24.56 | 0.42 | walk | 0.42 | ||
57 | 24.66 | 0.1 | deliver | 0.1 |
Statistic | Walk Δt1i | Deliver Δt2i | Total |
---|---|---|---|
Min | 0.35 | 0.09 | |
Max | 0.68 | 0.12 | |
Median | 0.43 | 0.1 | |
Average | 0.44 | 0.1 | |
Std Dev | 0.07 | 0.01 | |
CV1(Std Dev/Avgx100%) | 16% | 10% | |
95%tile | 0.53 | 0.12 | |
Performance Rating2 | 110% | 100% | |
Normal Tme3 | 0.48 | 0.1 | |
Allowance (20cm of snow) | 20% | 0% | |
Standard Time (per element)4 | 0.58 | 0.1 | |
Standard Time (per delivery)5 | 0.69 |
1(Std Dev/Avgx100%) 2based on bench marks, e.g., 3mph normal pace, and experience 3NT=Avg Observed Time x R/100% 420% of work or normal time. Total or ST = NTx(1+Allowance/100%) 5STtot=ST1+ST2 |