'Analysis of RF Fields Associated with Operation of PG&E Automatic Meter Reading Systems' (2005) https://www.pge.com/includes/docs/pdfs/shared/edusafety/systemworks/rfsafety/amr_rf_analysis_report_2005.pdf
Applicable RF Exposure Standards
Several guidelines or standards exist that recommend safe upper limits for human exposure to RF fields. These include limits developed by the Institute of Electrical and Electronics Engineers (IEEE, 1999), guideline published by the International Commission on Non-ionizing Radiation Protection (ICNIRP, 1998) and those promulgated by the Federal Communications Commission (FCC, 1997) relative to human exposure to RF fields 2 Of these, the exposure guidelines of the FCC are most relevant to the evaluation of potential exposure because the AMR system equipment is regulated by the FCC. The FCC maximum permissible exposure (MPE) values are tabulated in Appendix A and are usually expressed in terms of the plane wave equivalent power density of the RF field or the strength of the electric and/or magnetic field components of the RF field. Power density is expressed as power per unit area and is most commonly given in units of milliwatts per square centimeter (mW/cm2) or watts per square meter (W/m2). Electric field strength is specified in units of volts per meter (V/m) or, sometimes, microvolts per meter (μV/m), or in decibels relative to a microvolt per meter (dBμV/m) . The FCC exposure limits are, strictly, applied to FCC licensees such as operators of radio and television broadcast stations, two-way radio communications systems, cellular telephone base stations, etc.
Therefore, the decibels are compared to the MPE limit; for example, a va lue of 0 dB means an RF power density (RF field) value equal to the MPE. A value of -10 dB means the AMR device produces an RF field that is one-tenth of the MPE, -20 dB is 1/100 of the MPE, -30 db is 1/1000 of the MPE, and so forth. The results are also provide d as power density in units of microwatts per square centimeter (μW/cm2)
Installed Microwave Oven- FDA Allowable 5,000 μW/cm2
Wireless Local Area Network @ 2 ft 13 μW/cm2
Cell Phones @ head 1,000 – 3,000 μW/cm2
Walkie-Talkies @ head 500 – 10,000 μW/cm2
APPENDIX A - LIMITS FOR MAXIMUM PERMISSIBLE EXPOSURE (MPE) Adopted by the Federal Communications Commission (Reference = Table 1. Title 47 CFR)
The United States Federal Communications Commi ssion (FCC) first adopted guidelines to be used for human exposure to RF emissions in 1985. The FCC revised and updated their guidelines August 1, 1996, as a result of a rule-making pr oceeding initiated in 1993. The FCC Office of Engineering and Technology issued a new Evaluating Compliance document OET-Bulletin 65 in August 1997. The new guidelines incorporate limits for maximum permissible exposure (MPE) in terms of electric and magnetic field strength and power density for transmitters operating between 300 kHz And 100 GHz.
(FCC has two standards: occupational standard and public standard. The public standard is on page 19.)
30 - 300 MHz power density .2 mW/cm2.
300 - 1500 MHz = 1.5 GHz power density is given in MHz 1500
1500 - 100,000 MHz = 1.5 GHz - 1,000 GHz power density 1 mW/cm2 = 10W/m2