[BC] RF Compliance & Safety

[Alan Gearing]

Kevin:

You're welcome.  The main areas where stations seem to come a cropper 
with respect to RF exposure and the FCC are:

1) Failure to keep the tower base fence and/or ATU cabinet door closed 
and locked
2) Failure to keep the tower base fence in a sufficient state of repair 
so that it remains an effective barrier
3) Failure to have posted adequate warning signs - either wrong type or 
format, insufficient number of signs, or improper placement.  There are 
a number of sources for acceptable warning signs - including the NAB at 
one point, don't know if they still sell the signs or not.  As for 
number/placement, the general guideline is that no matter from which 
direction someone might approach the tower, a warning sign should be 
readily visible.  The site RFSigns.com has a rather good tutorial on the 
kind of things to consider when deciding which type of sign to post 
where.  (And don't forget the ASR sign if your tower is registered and 
any appropriate High Voltage warning signs.)

Regards,

Al Gearing

Kevin Raper wrote:
> Alan Gearing wrote:
>    
>> The "bible" for guidelines, equations, graphs, etc. for complying with
>> the Rules is OET Bulletin 65 (Edition 97-01 updated August 1997),
>> downloadable from the following URL:
>>
>>      http://www.fcc.gov/oet/info/documents/bulletins/
>>
>>      
> Thanks! That is just what I needed. Somebody sent my GM a scary sounding
> email about this, wanting to sell him "FCC Required Training" about RF
> Safety. and had him really freaking out about it.
>
>    
>> As for your specific question, depending on frequency and tower height a
>> 1 kW ND would require a compliant base fence at least 1-2 meters from
>> the tower/feed line (or other energized surface) and for a 5 kW ND the
>> distance would be at least 2 meters (for really short towers - much less
>> than 0.25 wavelength - these distances would be greater).
>>
>> Hope this helps.
>>
>>      
> That helps a LOT! WCKI's tower fence is about 15 Feet from the Tower,
> and WQIZ's fence is about 10 Feet, so we are safe. :-)
>    

-- 

####################
Alan E. Gearing, PE
Mullaney Engineering, Inc.
PH: 301-921-0115
FX: 301-590-9757
email: AEGearing at TZSawyer.com