i have another thought. so i would assume a spartan would need a greater percent of oxygen for those big muscles of theirs (like the dinosaurs) & a little poot poot could be catastrophic when fighting an elite in their halo suit. so do you think an ordinary respirator would do or in the future they just plug a carbon filter right to their sphincter?
[Edited on 12.23.2011 2:06 PM PST]