Because our EMT-IV does not meet the full standards for EMT-I/85 which includes cardiac monitoring, and the administration of drugs that are not within the EMT-IV scope of practice. Therefore, the state of Tennessee tests at the NREMT-B level. TN EMT-IV can now transmit a 12 lead in the presence of a paramedic, but they cannot initiate any kind of cardiac monitoring on their own, and certainly cannot interpret it.
There is more to i/85 training. Even though TN trains our lowest level provider at a level that far exceeds that of an EMT-B, the EMT-IV still is not considered an "Advanced Life Support" provider. As such, the state of tennessee tests the EMT-IV using the National Registry EMT-B examination.