"yes, you do. You also will have to do the 5 criticals from the other 2 organizations as well (so 15 total).  It's just like the requirements for the Flame Virus, Fly Virus, Fly Storm, and Blue Headlamp."

It's approx. 45 missions in total to get your 1 minute effect. Each chapter is split into three sub chapters (5.1, 5.2 and 5.3 in this case) each sub chapter has approx. 15 missions in total (usually five per organisation). You will need to run all those missions to get the item. Lets say that you can run each critical mission at six mins. a go (highly unlikely really), but if you could it would take you about four and a half hours to run all of them. It's more likely to take you around ten to 15 minutes per mission depending on hostile spawns, difficulty level (which is randomly selected) and total mission phases. So really you're looking at around seven to eight hours of missions in order to get a 1 minute effect which you can use only around 12 times an hour. Hmm. Fun.

Edited because these forums are crap.