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Standards for underwater manual metal arc welding


Frequently Asked Questions

The most common standard applicable to underwater welding is AWS D3.6M:2010 'Specification for underwater welding', published by the American Welding Society.

The standard covers requirements for welding structures or components under the surface of the water. It includes welding in both dry and wet environments.

The standard sets out three, individual classes of weld:

  • Class A - Comparable to above-water welding
  • Class B - For less critical applications
  • Class O - To meet the requirements of another designated code or specification

Note: the 1999 edition of the standard included Class C, which has been removed from the 2010 edition.

Copies of the standard are available from the American Welding Society ( and other websites that sell international standards.

For more information please email: