# Classification society

> An organization that sets technical standards for ship construction and maintenance and surveys ships against them.

## Record

- Record type: Encyclopedia entry
- Canonical page: https://admiralsatlas.com/en/organizations/classification-society/
- Last updated: 2026-08-31

## Article

A classification society is a non-governmental organization that establishes technical rules for the design, construction, and maintenance of ships, and verifies compliance through surveys throughout a vessel’s life. A ship meeting the rules is “in class” — a status that insurers, financiers, charterers, and flag states all rely upon.

The major societies — including DNV, Lloyd’s Register, the American Bureau of Shipping (ABS), Bureau Veritas, ClassNK, and China Classification Society — cooperate through the International Association of Classification Societies (IACS), whose members class the overwhelming majority of world tonnage.

Class surveys follow a five-year cycle (annual, intermediate, and special surveys), with the special survey being the most extensive. Losing class — through unrepaired damage or overdue surveys — typically voids insurance cover and breaches charterparty and mortgage terms.

Flag states also delegate statutory work to classification societies as recognized organizations, authorizing them to issue SOLAS, MARPOL, and Load Line certificates on the state’s behalf — making class societies, in practice, the technical backbone of maritime regulation.

## Related records

- [Flag state](/en/regulation/flag-state/index.md)
- [ISM Code](/en/regulation/ism-code/index.md)
- [SOLAS](/en/regulation/solas/index.md)