×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Why are standards for RF exposure what they are?

Why are standards for RF exposure what they are?

Why are standards for RF exposure what they are?

(OP)
So it's been 8 years since thread239-391830: How reputable is it to use RF for wireless charging? but I'm involved in this topic and it piqued my interest while I was browsing. It seems like the conclusion to that thread was similar to a nonconstructive "proof" saying that either the company was lying/misleading with the power numbers and even if they weren't lying the power number would be above maximum permissible exposure from regulatory agencies (FCC).

So I did some reading on RF exposure safety trying to elucidate the statement made by VEBill:

"The science behind RF safety is sufficiently mature that one can calculate the radius of exclusion from various sources without needing to go digging into the journals to prove it all again."

But I'm struggling to actually understand said science. If the concern is dielectric heating, how can a Watt scale system produce heating that's actually concerning (aren't permissible exposure limits based on W/kg anyways)? I'm not talking about the regulatory hurdles involved in commercial realization of a system, I mean the actual health/safety concerns.

As in, when something like "The whole wireless power concept is deeply flawed. Because the gap between the practical and the safe is so small." is said, is "the safe" defined as allowed by the regulatory body? Please forgive me if I'm missing something; I would gladly appreciate some rough numbers/back of envelope calculation if I am. To me, I just don't understand how 1-10W of narrowband RF is relevant compared to the 1300 W/m^2 blackbody shining down from outside or even the 100W incandescent bulb. Is the concern that the unknown unknown of high spectral density is an issue?

Thanks

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Resources

Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close