I'm not clear on the task. Is this primarily:
- gathering data so that you can tell your manager, "Our workers get an average of fourteen interruptions a day! You have to do something!"
- doing the "do something!"
Either way, I think that one of the most important parts is that the tracking be as easy as humanly possible for the individual in the moment, EVEN IF that means that someone else has to do some work later.
For example, if it's a pure data-gathering task, then rather than requiring that people log into a database and enter six required fields, let them send an email with just a few words ("info request from HR") to a specific address. That could mean that someone has to sit down for two hours every week to paw through those emails and figure out what they mean and enter them into a database or spreadsheet, but that's one task performed by a person who knows the task, and is likely to waste fewer total personnel minutes than repeated instances of "What's that database again?", "Dang, I forgot my password", "What am I supposed to enter in this field again?", "Oops; I haven't entered any interruptions at all into the database this week. I'll just make some up."
Digression: This is part of an overall pet peeve of mine, where businesses try to make a task more distributed than it absolutely must be, on the theory that it will save time, when it actually costs time. It makes sense to think that each person should do his own bleeping paperwork, but it's often better to have someone else, someone for whom that paperwork is closer to the core of their job, do it instead. If there's no obvious or fair candidate, one member of a team could be the paperwork person for three or six or twelve months at a time.