Which chart scale is used for Harbor?

• A. 1:40,000 and larger
• B. 1:60,000 and larger
• C. 1:50,000 and larger
• D. 1:150,000-600,000

Answer: (C)

In navigation, chart scale shows how much area is shown and how much detail you get. Harbor navigation needs a large-scale chart, which means a chart ratio of 1:50,000 or larger (numerically smaller than 1:50,000). This level of detail lets you clearly see channels, depths, shoals, aids to navigation, mooring areas, and hazards in confined waters. So the Harbor category uses 1:50,000 and larger. Scales like 1:150,000–600,000 cover too wide an area and lack the nearshore detail needed for safe harbor piloting, while 1:60,000 sits closer to a large-scale range but the standard threshold for harbor use is 1:50,000 or larger.