AlON pressure barrier
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Some UNSC warships have been seen to incorporate a retractable AlON pressure barrier into the decks of their hangar bays. In the event that the crew must perform a funeral service with the deceased committed to space, the pressure barrier can rise out of the deck to seal off the interment capsules from the rest of the hangar. Then, the outer hatch can be ceremoniously opened to allow the capsules to be launched into space while keeping the burial detail and honor company safe from decompression. When the service is over and the outer hatch is closed, the AlON pressure barrier can simply sink back into the deck.
After the Battle of Seoba in March 2526, the UNSC Vanishing Point held a funeral service for the two-hundred-and-three naval personnel that had been lost. The ceremony was held in the vessel's command hangar with the interment capsules positioned near the outer hatch. Staff Sergeant Avery Johnson led the burial detail in raising the AlON pressure barrier and opening the outer hatch while Lieutenant Commander Hector Nyeto delivered a Committal speech in honor of the dead.
The AlON pressure barrier is likely made out of aluminum oxynitride, a transparent ceramic marketed under the name "ALON." Often used in military applications, the material is optically transparent, bulletproof, and blast-resistant.
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