Working on setting up a new HF station with 100W and beam antenna. Need to understand the RF exposure requirements under Part 97.13.

Questions:

• When is a routine environmental evaluation required?
• What documentation do I need to keep?
• How do I handle household vs. general population limits?
• Any good tools for calculations?

Before transmitting where operation could cause RF exposure exceeding limits in § 1.1310, licensees must take certain actions. OET Bulletin 65, Supplement B provides methodologies for amateur radio evaluation.

Household members can be evaluated using occupational limits, while others use general population limits. Keep your calculations on file - the FCC doesn't require submission but you need them for potential inspections.

I use the ARRL RF Exposure Calculator - makes the math easy for typical setups. Most 100W HF operations are compliant if you maintain proper distances. If fields could exceed limits in accessible areas, you must take action to prevent human exposure.