The OOC (out of combat) regeneration system was added in TSS and allows for extremely rapid regeneration of mana or health when not in a combat situation (3-4% of your total capacity health/mana per tick). This ensures it takes no longer than 3 minutes to fully regenerate from 1 health 1 mana to your maximum capacity. It was/is a dramatic reduction in idle down-time normally enforced during normal game play.
The OOC status is represented by a yellow/gold orb, blue orb, pair of crossed swords, hourglass or yellow/red tear.
There is a icon near your name & health/mana bar. When in combat it is crossed swords. When cooling down from combat it is an Hourglass and a 30 second timer displays and counts down. When out of combat and the timer has counted down, but you are moving around it is a blue orb. When debuffed (blocking OOC) the icon is a yellow/red tear. When in active OOC regeneration it is a golden orb.
You must be immobile and sitting (or on a mount) for OOC to kick in after the timer count-down.
You cannot enter OOC for five minutes after you lose aggro or kill a raid mob, and thirty seconds for a group mob.