Toyota Repair: failed smog test, voltage waveforms, smog test

Question
QUESTION: Hello,
My sons car, a 96 Toyota Corolla, just failed the smog test.  The numbers are:
15mph
RPM: 1831
%Co2 14.5
%02  0.1
HC (PPM)  97
Co(%)   0.43
NO (PPM)  24

25 MPH
RPM  1802
%CO2  14.4
%O2    0.0
HC (PPM)  74
CO (%)     0.54
NO (PPM)  19

Possible repair suggestions- without a diagnostic test- from Smog Technician is possible O2 sensor or catalytic converter. What are your thoughts?

Thank you,
Mary

ANSWER: I'm not a qualified smog tech, those numbers don't look that bad, what reading caused it to fail, what was the reason it failed?

---------- FOLLOW-UP ----------

QUESTION: The reason is in the HC (PPM)
15 mph Max should be 61
      Average        9
      Measured      97
25mph Max:          45
     Average         7
     Measured       74  
and in the CO(%)
25mph  Max         0.53
      Average     0.03
      Measured    0.54
These numbers are the ones circled that exceeded the max and which caused it to fail the test.  The tech stated that the engine was running fine that it wasn't missing and then stated the possibility of a 02 sensor or catalytic converter but first he would recommend a diagnostic test.

Answer
Higher than normal HC readings are normally caused by incomplete combustion due to a mechanical engine problem but they said the engine was not misfiring, in that case it may be an inefficient catalityc converter,if you are dealing with a test and repair facility I would recommend having them check the O2 sensor operation,this is done by reading the voltage waveforms of both the front and rear O2 sensors, this will determine if the cat is the problem or one of the sensors.