Some BiPolar Ion equipment manufacturers target 5,000-10,000 ions/cc for rooms. Particle emissions alone from a person sitting quietly are estimated at 212 particles/cc (p/cc) per minute. Just standing or sitting they will increase to 5,300 p/cc per minute, and active motion, such as fans at a game, increase levels by 63,500p/cc per minute; again – from a single person. https://bit.ly/2UvRDz2 (Calculated from slide 25 & assuming values are per second.)
One PureShield 800 can boost ion levels by producing up to 800,000,000 ions/cm2/second, and sanitize air immediately upon contact with UVC.