The breathing tube is made with separate ducts for the air inhaled and exhaled and the inside of the mask is made with two compartments, an upper main compartment (26) and a lower oronasal compartment (7) separated by a separating wall.
Masks for underwater uses
2020-02-11
Patent
Elektronische Ressource
Englisch
IPC: | B63C LAUNCHING, HAULING-OUT, OR DRY-DOCKING OF VESSELS , Zuwasserlassen, Trockenstellen, Docken oder Bergen von Schiffen |
Engineering Index Backfile | 1943
|Nanostructuring repairs lithographic masks
British Library Online Contents | 2000