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Subchapter 7. General Industry Safety Orders
Group 14. Radiation and Radioactivity
Article 104. Nonionizing Radiation

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§5085. Radiofrequency and Microwave Radiation.

(a) Definitions.

Radiofrequency (RF) Energy. Electromagnetic energy restricted to that portion of the spectrum commonly defined as the radiofrequency or RF region with frequencies between 3 megahertz (MHz) and 300 Gigahertz (GHz) and which for the purposes of this specification shall include the microwave region with frequencies between 100 MHz and 300 GHz. (Hertz = 1 cycle/second, MHz = 1 million hertz, GHz = 1 billion hertz.)

Exposure. Irradiation of any part of the body by incident RF energy.

(b) Exposure Limits. Employees shall not be exposed to RF energy from continuous wave or repetitively pulsed sources exceeding any of the following limits as averaged over any possible six minute (0.1 hour) period.

 (1) Continuous exposure to an average maximum power density of 10 mW/cm2 (milliwatts per square centimeter) or the equivalent free space average electric and magnetic field strengths of 200 V/M (volts per meter) rms and 0.5 A/M (amperes per meter) rms respectively. 

  (2) Exposure to interrupted or modulated RF energy shall not exceed: 

 (A) An average maximum energy density of 1 mW hr/cm2 (milliwatt-hour per square centimeter); 

 (B) A mean squared electric field strength of 4x104 (V/M) 2 (volts squared per meter squared); 

 (C) A mean squared magnetic field strength of 0.25 (A/M)2 (amperes squared per meter squared). 

 These energy densities and field strengths are approximately equivalent to a far field power density of 10 mW/cm2. 

(c) Information and Warning Signs. In areas where employee exposure may exceed the limits specified in part (b) of this section, employers shall provide warning signs containing the following information in the following manner:

 (1) Warning signs of RF radiation hazards, as described in ANSI C95.2-1966 "Radiofrequency Radiation Hazard Warning Symbol," containing the necessary information and description of required protective actions. (See Figure RF-1.) 

 (2) Signs shall be posted at all entrances to accessible areas containing RF radiation levels in excess of the exposure limits described in part (b). 

 (3) Warning signs shall be legible at a distance of ten (10) meters. 

Figure RF-1 (From ANSI C95.2-1966)

 1. Place handling and mounting instructions on reverse side. 

 2. D=Scaling unit. 

 3. Lettering: Ratio of letter height to thickness of letter lines. 

Upper triangle: .. 5 to 1 Large   
                   6 to 1 Medium  
Lower triangle: .. 4 to 1 Small   
                   6 to 1 Medium  
 4. Symbol is square, triangles are right-angle isosceles Radio-Frequency Radiation Hazard Warning Symbol 

    Note: Authority and reference cited: Section 142.3, Labor Code.  

1. New Article 104 (Section 5085) filed 4-16-81; effective thirtieth day
thereafter (Register 81, No. 16).

2. Change without regulatory effect providing more legible illustration for
Figure RF-1 filed 3-2-2009 pursuant to 
section 100, title 1, California Codeof Regulations (Register 2009, No. 10).

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