Could've & Should've given the URL for the PDF from whence Honeywell/F-35 OBOGS GIF graphic came: [same same OBOGS in Eurofarter & F-35/F-22]
https://aerocontent.honeywell.com/ae...rt_Systems.pdf (4Mb)
"...Typical System Architecture
A typical system is shown in Figure 4. [wot you see above in GIF grfx] The OBOGS is controlled by a solid state monitor/controller that monitors the PPO2 level of the OBOGS product gas, and adjusts the cycling of the beds to produce the desired level of oxygen concentration shown in Figure 2. [seen in PDF] This process is known as concentration control and means that no air-mix, or dilution, of the product gas is required at the regulator.
The breathing gas then passes to the pilot’s breathing regulator, either a console/panel-mounted, ejection seat-mounted or pilot-mounted device. The regulator is a demand flow regulator like those of GOX and LOX systems, differing only in the fact that they operate at lower pressures and do not air-mix. The final system element is a back-up oxygen cylinder mounted on the ejection seat to provide oxygen during pilot ejection, or in the unlikely event of an interruption in the OBOGS supply....
...Breathing gas purity – OBOGS regulators do not air-mix thus the pilot is not susceptible to smoke and fumes from the cockpit. Oxygen concentration is controlled inside the zeolite beds and is hence free from contamination...."
Quote from 2 page PDF attached about the MB F-35 Ejection Seat:
http://militaryrussia.ru/forum/downl...e.php?id=28256 (PDF there no longer available)
"...The catapult houses a 300L backup oxygen system (BOS) which can be removed or re-charged on the seat. Both the SCP and BOS are supplied by Honeywell Aerospace based in Yeovil, Somerset, UK...."