Also keep in mind that the scanner technology at the two airports is very different. RDU has the RF MMW scanners which are almost certainly harmless and have less resolving power. So the resulting images are not as clear and detailed. BOS has the xray scanners which are almost certainly not harmless and the resulting images are clear, detailed, and very explicit. The consequences in terms of both privacy and health are more serious. Just something to keep in mind when deciding whether to opt out.