Chart Corrections
Charts must be kept up to date — new hazards, changed buoys, altered depths, and other changes are published in Notices to Mariners (NMs). Professional vessels correct charts weekly using these notices.
For leisure sailors, chart correction sets are available from chart agents. Alternatively, keep charts current by purchasing new editions when they are published. Electronic charts on plotters are updated via software downloads.
Key Points
- Notices to Mariners (NMs) publish chart corrections
- Always check chart edition date — older = higher risk of errors
- Electronic charts: update via software/downloads
- Corrections are made in waterproof violet ink on paper charts