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Radio students of Nathan Hale High School (Lake City, Seattle)'s KNHC-FM under Entercom's tower at Cougar

As long as nobody is hanging around above with stuff that could fall...
then they would all need hardhats!

Otherwise, the FM antenna is a couple hundred feet above them, moreover, that site is considerably "displaced" from the infamous "Ratelco
Site One"................where an RF suit is required if you are more than 20 feet above ground to keep the RF exposure down to a dull roar.

Most broadcast antennae radiate a gain pattern, thus RF is nulled directly above and below... As each leg of that tower is bonded into a ground ring I would say where the students are located is likely the safest place to be in terms of RF exposure.

If there were even the remotest threat of a lightning strike then you would want to be as far from any metal as you could get... regardless of how well it is grounded, a direct or even a nearby strike would induce significant and deadly voltages!!!

Eric
KB7DQH

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That is how the people at DARPA think. they take things and use them in unconventional ways, to see what happens.

The FCC still REQUIRES that all FM broadcast stations reduce power or stop transmitting -- anytime workers (or persons) are close to the tower. They all should still be able to have children someday. I can't say the same for two young workers that climbed the old KMPS/KZOK/KRAB tower on Cougar Mtn - many years ago. It was snowing lightly and both had to remove coats and shirts -- it was so hot at the top of the 200 foot tower. All 3 stations were at full ERP of 100 KW each.

We are required to call in and have power turned down on broadcast when we are on the tower. Specifically within 50 feet of the broadcast antenna.

The site owners and high power tenants are required to post the site depending on the rf levels. So...

The "CAUTION" sign is appropriate where individuals may have access to areas in which the RF fields exceed the occupational Maximum Permissible Exposure (MPE) limits in controlled areas.

The "NOTICE" sign may be used in areas where RF fields exceed the Maximum Permissible Exposure (MPE) limits for the general public in uncontrolled areas.

The WARNING sign should be used in those areas, very near RF sources, in which RF fields may substantially exceed the controlled environment Maximum Permissible Exposure (MPE) limits by ten times or more. (you really need a personal rf sensing device if this sign is posted.

So more than anything the "safety person" (the teacher?) should know the signs and the rules. They may just simply need to limit their exposure to a couple of hours max. Or long enough to shoot the picture... :shock:

But generally the ground will see the lowest rf. Tower climb gates will generally be posted with the higher "notice" or "warning" sign if needed.

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"A well regulated breakfast, being necessary to the healthy start of the day, the right of the people to keep and eat food shall not be infringed."

Now, if it were an AM broadcast tower, they wouldn't want to be touching the tower...

Those are usually, (but not always) fenced off around the towers themselves.