American Nautical Services, an ISO 9001-certified ADMIRALTY chart agent in Fort Lauderdale, supplies paper charts corrected to date at the moment they leave the chart room. From that day on, keeping them current is the ship's job. Maintaining paper charts aboard comes down to three disciplines: correcting every chart from the weekly Notices to Mariners, storing the folio so charts stay flat, dry, and findable, and recording each correction so the navigator and any inspector can see the chart's status at a glance.
Why Paper Chart Maintenance Still Matters
Paper remains the primary chart system on many ships and the backup on many more. The UK Hydrographic Office committed in February 2026 to supplying ADMIRALTY paper charts for as long as they are needed, with no withdrawal date, as covered in the ANS update on paper chart withdrawal. That means paper folios will be aboard, and inspected, for years to come.
The regulatory test is simple. SOLAS Chapter V, Regulation 27 requires nautical charts to be adequate and up to date. A chart that is the current edition but missing three weeks of corrections fails that test as clearly as an outdated edition does. Two failures account for most chart deficiencies:
- A superseded edition still in the folio
- A current edition with Notices to Mariners not applied or not recorded
How Are Nautical Charts Corrected From Notices to Mariners?
Charts are corrected by hand from the weekly Notices to Mariners (NMs) issued by the hydrographic office that publishes each chart. ADMIRALTY charts take ADMIRALTY NMs, issued weekly by the UKHO. US charts take the weekly US Notice to Mariners from the National Geospatial-Intelligence Agency, supplemented by US Coast Guard Local Notices to Mariners. The ANS guide to Notices to Mariners explains how each weekly booklet is structured.
Step-by-step correction procedure
- Confirm the edition. Check each chart against the Cumulative List of ADMIRALTY Notices to Mariners (NP234), published twice a year. A chart with an earlier edition date than the one listed is cancelled and must be replaced, and NMs never apply to it.
- Identify the charts affected. Use the index of charts affected in the weekly NM to identify every folio chart the week's notices touch.
- Apply permanent corrections in ink. The UKHO recommends a very fine pen, preferably magenta, so corrections stand out from the printed detail. Some fleets still specify violet waterproof ink, so follow the SMS.
- Insert before you delete. Add the new symbol or text first, then strike through the old information with two diagonal lines.
- Paste blocks where supplied. For complex changes, cut out the printed block, trim its black border, and fix it at the stated position with a permanent glue stick.
- Record the correction on the chart. Write the NM year and number in the bottom left-hand corner of the chart, and only after the correction is complete.
- Plot temporary and preliminary (T&P) notices in pencil. Erase them when the cancelling notice arrives.
- Log the correction. Enter it in the chart correction log before closing out the week.
A chart correction template with IALA buoyage stencils keeps symbols consistent, and Symbols and Abbreviations Used on ADMIRALTY Charts (NP5011) settles symbol questions. The UKHO's own manual, How to Keep Your ADMIRALTY Charts Up-to-Date (NP294), is the reference for the full procedure.
The weekly correction routine
| Interval | Task |
|---|---|
| Every week | Obtain the weekly NMs, apply corrections to every affected folio chart, update T&P notices, record in the log |
| Before each voyage | Confirm every chart for the passage is the current edition and corrected to the latest NM |
| Twice a year | Check the full folio against the new Cumulative List (NP234) |
| Every January | Review the Annual Summary of ADMIRALTY Notices to Mariners (NP247) for annual notices and T&P notices still in force |
Proper Storage and Handling Aboard
A corrected chart is only useful if it survives to the next passage legible and findable. Standard practice aboard commercial ships follows a few rules.
Do:
- Store charts flat in chart table drawers, arranged by ADMIRALTY folio number so each chart has a fixed home
- Keep the chart in current use flat on the chart table, held with chart weights rather than tape
- Plot passages with a soft pencil and erase lightly, so the chart surface and printed detail survive repeated use
- Keep the chart room dry and away from direct sunlight, which fades color and makes paper brittle
- Remove cancelled charts from the folio as soon as replacements arrive, and mark them clearly if retained for reference
Avoid:
- Rolling charts, which then refuse to lie flat on the chart table
- Folding charts more than their supplied fold
- Hard pencils pressed heavily, which score the paper and leave grooves after erasure
- Mixing folios or leaving "loose" charts on the bridge after a passage
Smaller vessels without chart drawers can protect charts in clear waterproof wallets, but the folio-by-number principle still applies. Pens, pencils, and erasers are grouped in the ANS pens and pencils collection.
Keeping a Chart Correction Log
The chart correction log is the record that ties the folio together. For each chart, it shows the edition held, every permanent NM applied, and each T&P notice in force. An inspector can read it in minutes, and a relieving officer can take over the folio without guesswork.
The UKHO's Paper Chart Maintenance Record and Chart Correction Log (NP133A) is the standard format for ADMIRALTY folios. An illustrative entry, with example chart and notice numbers, looks like this:
| Chart | Edition date | NM applied | Date applied | Initials |
|---|---|---|---|---|
| 2837 | 12 Mar 2025 | 3412/26 | 30 Sep 2026 | 2/O |
| 2837 | 12 Mar 2025 | 3480(T)/26, pencil | 30 Sep 2026 | 2/O |
For US charts, chart correction card published by the NGA serve the same purpose, card by card.
SOLAS does not prescribe a specific log format. Port state control officers and vetting inspectors do ask for evidence of correction status, and a maintained log, whether NP133A or an equivalent required by the ship's SMS, is the normal way to provide it.
Shop Chart Correction Logs and Templates
Corrected charts, a disciplined weekly routine, and a complete log are what turn a paper folio into a compliant one. ANS supplies ADMIRALTY and NOAA charts corrected to date along with the publications and tools to keep them that way.
Shop chart correction logs and templates, starting with the NP133A Chart Correction Log, or contact ANS at +1 (954) 522-3321 or sales@amnautical.com for corrected charts and folio reviews.
Frequently Asked Questions
How often should paper charts be corrected?
Every week, as each Notice to Mariners is issued. Before each voyage, every chart for the passage should also be confirmed as the current edition and corrected to the latest notice.
How are nautical charts corrected?
Charts are corrected by hand from Notices to Mariners: permanent corrections in fine ink, temporary and preliminary notices in pencil, printed blocks pasted where supplied, and the NM year and number written in the chart's bottom left-hand corner.
What's the best way to store chart folios on a vessel?
Flat in chart table drawers, organized by folio number, kept dry and out of direct sunlight. Rolling charts and adding extra folds should be avoided.
Do I need a chart correction log for PSC inspections?
SOLAS does not mandate a specific log, but inspectors expect evidence that charts are up to date. A maintained chart correction log, such as NP133A, is the standard way to show it.
What happens to Notices to Mariners when a new edition is published?
Notices apply only to the edition currently in force. When a new edition is published, the old chart is cancelled, and corrections start fresh on the new one.
What ink should be used for chart corrections?
The UKHO recommends a very fine pen, preferably magenta, for permanent corrections. Some companies specify violet waterproof ink in their SMS. Temporary and preliminary notices are always plotted in pencil.
