Hierarchy classification:

1. top of the aat hierarchies
2. Objects Facet
3. Furnishings and Equipment (hierarchy name)
4. Recreational Artifacts (hierarchy name)
5. recreational artifacts (equipment)
6. [temporary alphabetical list: recreational artifacts]

Anotations

Scope note:

Headgear used to protect and to provide a steady supply of oxygen for the user. Used for both shallow-water and deep-water diving. Early examples from the 19th century were commonly made of metal and featured several portholes for viewing, covering the entire head. Contemporary helmets are made of various materials (metal, plastic, fiberglass, etc.) and provide a single transparent viewer to aid sight.