
Appendix D
Operator
’s Guide
RJS, Minneapolis, MN
003-4500
74
Table D-2 (Symbol Contrast percentage ranges to
Numeric and Letter Grades)
Min
Max
Numeric
Letter
70
100
4.0
A
69
69.99
3.9
A
67
68.99
3.8
A
66
66.99
3.7
A
64
65.99
3.6
A
63
63.99
3.5
A
61
62.99
3.4
B
60
60.99
3.3
B
58
59.99
3.2
B
57
57.99
3.1
B
55
56.99
3.0
B
54
54.99
2.9
B
52
53.99
2.8
B
51
51.99
2.7
B
49
50.99
2.6
B
48
48.99
2.5
B
46
47.99
2.4
C
45
45.99
2.3
C
43
44.99
2.2
C
42
42.99
2.1
C
40
41.99
2.0
C
38
39.99
1.9
C
36
37.99
1.8
C
34
35.99
1.7
C
32
33.99
1.6
C
30
31.99
1.5
C
28
29.99
1.4
D
26
27.99
1.3
D
24
25.99
1.2
D
22
23.99
1.1
D
20
21.99
1.0
D
18
19.99
0.9
D
16
17.99
0.8
D
14
15.99
0.7
D
12
13.99
0.6
D
10
11.99
0.5
D
8
9.99
0.4
F
6
7.99
0.3
F
4
5.99
0.2
F
2
3.99
0.1
F
0
1.99
0.0
F