Our landlord requires that as the management company for a commercial office building, we take panel load readings for each hour for 7 days, before adding load to a panel. We bought the meter; the in-house electrician brings me the readings on a chip and I have to reformat them to send to the landlord prior to our doing work. So if the panel is rated at 225a, and A leg has a MAX load of 32.77 a, the B leg has a MAX load of 21.62 and C Leg has a MAX load of 49.88, is the total MAX load for the panel 104.27?

No, the amperage is not cumulative. It's just A, B & C.

kaa,
Please review the electrical code article 220.87... this is what should be required by the electrical subcode official before allowing the landlord's to add load to their buildings.

What is the voltage and phase of this 225A panel? 208V, 3 Phase or 480V 3 Phase?
If you multiply the A phase voltage x the A phase amperage = A phase power in Watts...
do the same for each phase and then add them for a total.

The concept of "maximum" load is relative to the time the load is measured. In the summer the HVAC load is a large part of most service loads. In the winter the measured load will be 40% to 60% less, unless you have electric heat.

So be careful of the panel you are measuring and take note of the time of year and the possible equipment that may be connected but not running. Emon Dmon demand meters that record load over a years time are good reference.

I forgot to mention that to be more accurate you need to measure also the "power factor" of the load you are measuring...