How much is a diving helmet worth?
The average price of an American-made helmet runs between $3,000 and $10,000. A vintage Mark V helmet sells for between $6,000 and $10,000.
How does a scuba helmet work?
The diving helmet works like a glass turned upside down in water. As long as the open end is held downward, the air is cupped underneath. This is similar, but opposite, to how a glass contains water, when held right side up in air. The collar of lead at the bottom keeps the padded, open end, down.
How deep can you dive without a helmet?
For most swimmers, a depth of 20 feet (6.09 metres) is the most they will free dive. Experienced divers can safely dive to a depth of 40 feet (12.19 metres) when exploring underwater reefs. When free diving the body goes through several changes to help with acclimatisation.