[SFDXA] More detail about the 2020 changes to FCC RF Exposure Rules

[Kai]

On 5/7/2020 10:09, Richard Gillingham wrote:
> Kai, I was distracted when you told us about recent FCC activity on hand-held 
> radios.
> Could you post that for us? I missed most of what you had to say.
>
> Thanks
> Gil, W1RG
Gil,
Here is additional detail about my report to the SFDXA on-air meeting of 6 May 2020.
Preliminary Report on Changes to FCC RF Exposure Rules, 2020, courtesy of the 
ARRL RF Safety Committee.

How Radio Amateurs Must Evaluate Human Exposure from their Stations Differently 
Beginning June 1, 2020:

FCC Human Exposure Rules
• Originally released in 1998
• Radio amateurs were introduced to human exposure limits for the first time
• ARRL published 'RF Exposure and You'
• Minor rule changes were made in 2013, but no changes for Radio Amateurs

FCC Human Exposure Rules Updates
• New rule changes were published in the April 1, 2020 Federal Register
• New rules take effect June 1, 2020
• Rule changes to 47 CFR Parts 1, 2, 15, 18, 22, 24, 25, 27, 73, 90, 95, 97 and 101
• Amateur Radio Service is affected by Parts 1, 2, and 97

What Has Changed
• Amateurs No Longer Have Categorical Exclusions to Evaluation
• Stations with power at the antenna input below certain limits
     did not have to perform routine evaluations.
• No mobile transmitters had to perform routine evaluations.
• New Exemptions to Routine Evaluation are based on frequency,
     power and distance.
• All transmitters/emitters that are within 20 cm of the body must be
     evaluated with SAR (Specific Absorption Rate).
• SAR modeling is accepted in addition to SAR testing.

New Exemptions
• Based on ERP and frequency
• New formulas used for antennas closer than 40 cm to a person,
     exceeding the levels in the new formulas determines if SAR
     Evaluation must be performed

What about HTs?
• The 2 m HT is not covered under the new Exemptions:
• Its antenna is within 20 cm of the head
• Its frequency is < 300 MHz
• No known SAR tests have been performed with Amateur HTs
• SAR testing is too complex for most hams to perform
• SAR modeling is also too complex for most hams to perform
• Newly produced amateur HTs will have to be characterized
     by their manufacturers for SAR

How Will Hams Follow the Rules Going Forward?
• Fortunately, the new rules have been released with a 2-year
     transition period.
• The FCC’s aids for following human exposure rules:
     OET Bulletin 65 and OET Bulletin 65 Supplement B for Radio
     Amateurs will have to be revised.
• The ARRL RF Safety Committee is working with the FCC
     personnel to revised these documents.
• ARRL is working on finding or developing tools that all hams
     can use to perform exposure assessments.

With kindest regards,
Kai Siwiak, KE4PT
Member ARRL RF Safety Committee