Help deciphering these stats, thanks

I'm having trouble deciphering these statistics and I don't want to say someone is wrong then it turns out I'm the one not getting it:

So the cited source says:

Quote:

Results: From these data, the expected number of annual occupational hepatitis C virus seroconversions was estimated to be between 5.8 and 118.9 per 100,000 employee-years for EMT-paramedics, between 3.4 and 33.7 per 100,000 for firefighter-EMTs, and up to 3.6 per 100,000 for firefighters (non-EMT).

The source (NFPA Standards) that uses that cite says:

Quote:

Prehospital Emergency Care, the expected number of annual occupational hepatitis C seroconversions for firefighter/EMTs was estimated to be 3.4 to 33.7 per 100,000.

I'm sure that bottom number is wrong because I know the rate for seroconversion to hep C is much much lower than that. And 100,000 employee (person) years is not "annual seroconversion" rates.

But it's in the NFPA Standards and that's a big deal. I'm afraid I must be missing something. Before I bring this up to the EMS Coordinator at the fire department (a battalion chief position), I want to be sure I'm right because I'll look very foolish if I'm not.

Thanks in advance. :)

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