Again--a short version --Evaluating means doing the math to determine the RF levels where people are. The League has a nice RF exposure "do it yourself" document that can be found on line.
Here are some downloadable docs pretty much in plain language
OET Bulletin 56 - Questions and Answers about Biological Effects and Potential Hazards of Radiofrequency Electromagnetic Fields
OET Bulletin 65 - Evaluating Compliance with FCC Guidelines for Human Exposure to Radiofrequency Electromagnetic Fields
A Local Government Official’s Guide to Transmitting Antenna RF Emission Safety: Rules, Procedures, and Practical Guidance
Electromagnetic Energy – Evaluation and Management for Antenna Sites (Motorola)
The FCC docs are at:http://www.fcc.gov/oet/rfsafety
OET 65 has the do it yourself tables and calculations. The Local government's guide is written for, shall we say, "non-technical" persons.