Minimum safe distance to a Aironet 1242AG

Question

To whom it may concern,
I've been trying to conduct safety studies on RF systems I'm using on a project, one of which is the Cisco Aironet 1242AG. The FCC's OET states that for the 2.45GHz frequency range, an RF exposure of 1mw/(cm^2) is acceptable for non-controlled RF. I ran a few calculations for our Aironet coupled with a high gain antenna (15dBi) and determined the minimum safe distance was 4.2" away from the antenna. However, standard documentation in the Quick Start Guide for the Aironet 1240AG series access point claims the minimum safe distance is 7.9". I'm trying to figure out how that 7.9" figure was arrived at. The high gain antenna in use is omnidirectional with a beam height of + - 8 degrees.
The answer is important to me because we have our antenna mounted near a place where a human could sit. Part of me wonders if 7.9" was arrived at simply because the FCC OET Bulletin 65 Supplement C mentions devices with external omni-antenna being typically mounted 20cm away from where a human could be (pg.19).
Any insight would be great to this.
- jevans

Answer 1

I think the line "Proper installation of this radio according to the instructions found in this manual will result in user exposure that is substantially below the FCC recommended limits" clarifies the fact that FCC recommended and cisco recommendation is different taking human safety into account.