The NFPA 4-hour load test is NOT a generator test. It is designed to test the entire emergency power system. It tests all of the transfer switches, emergency circuit breakers, electrical connections, and emergency egress lighting, in addition to the generator.
The loadbank is only supplemental. It is not the whole test. Many generator companies only test the generator. Insist that your provider follow NFPA 110, chapter 8.4.9.
Please see my video: How to Conduct a 4-Hour Load Test
I have posted a suggested 4-hour Load Test Form.