Natural error
Personal error
Artificial error
Instrumental error
+/- 2 mm
+/- 4 mm
+/- 6 mm
+/- 8 mm
Linen tape
Steel tape
Invar tape
Metallic tape
15 feet and 30 feet
30 feet and 45 feet
45 feet and 60 feet
50 feet and 100 feet