Chart No. 1 · K 29
Non-dangerous wreck
Dangers
The same hull-and-ribs symbol without a danger circle: a deep wreck safe for surface navigation.
What it means
The hull-and-ribs wreck symbol without a danger circle marks a wreck whose depth is unknown but which is considered deep enough not to endanger surface vessels (typically deeper than about 20 m).
Why it matters
'Non-dangerous' applies to surface navigation only — it still matters to anyone anchoring, trawling, or diving. The presence or absence of the dotted circle is the whole difference from K 28.