| ViewingDistance | Minimum RequiredLetter Height |
| 100 ft. | 4 inches |
| 250 ft. | 10 inches |
| 360 ft. (city block) | 16 inches |
| 500 ft. | 22 inches |
| 750 ft. | 33 inches |
| 1000 ft. | 43 inches |
| 1320 ft. (1/4 mile) | 57 inches |
| ViewingDistance | Minimum RequiredLetter Height |
| 100 ft. | 4 inches |
| 250 ft. | 10 inches |
| 360 ft. (city block) | 16 inches |
| 500 ft. | 22 inches |
| 750 ft. | 33 inches |
| 1000 ft. | 43 inches |
| 1320 ft. (1/4 mile) | 57 inches |