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Comment Re:Safety (Score 1) 63

They may be, given the horrendous loss involved and the use of directional coupling. That 50 Watt limit is not absolute, it's more of a guideline for Amateur radio stations specifically, not all emitters. Your cell phone at < 4W is also closely regulated due to its proximity to human tissue. Please refer to the FCC RF exposure site for the full regs.

RF exposure is a function of frequency, duty cycle, distance, transmitter power, and antenna gain. I have a tiny 10mW 10GHz transmitter that couples its power via WR-90 waveguide. If my math is correct, that's 3.1 mW/cm^2 at the mouth of the waveguide - WAY over the exposure limit of 1.0 mW/cm^2 at 10 GHz for uncontrolled access.

Remember, sunburns are actually RF burns.

Comment Re:Safety (Score 1) 63

Magnetic fields don't hurt you

STATIC magnetic fields don't seem to hurt you. Time-varying magnetic fields most certainly can hurt you. In addition to ionizing radiation (x-rays, gamma rays) which can obviously hurt you, plain old radio waves can too:

Radiation burns can also occur with high power radio transmitters at any frequency where the body absorbs radio frequency energy and converts it to heat.[1] The U.S. Federal Communications Commission (FCC) considers 50 watts to be the lowest power above which radio stations must evaluate emission safety. Frequencies considered especially dangerous occur where the human body can become resonant, at 35 MHz, 70 MHz, 80-100 MHz, 400 MHz, and 1 GHz.[2] Exposure to microwaves of too high intensity can cause microwave burns.

Comment Re:Might make sense (Score 1) 87

I agree with your points - they're all well-reasoned.

What I haven't seen mentioned is the case where the drone arrives first and it's video shows the dispatchers that the fire is much larger/more involved than first reported so the dispatcher can roll additional equipment to the scene while the original trucks are still en route. That would be a major plus for having the drones.

Similarly, if the drone finds that the original report of a massive fire is more like a tiny shed on fire, they could cancel some of the equipment en route, freeing it up for other calls.

Another case: A train derailment or tractor-trailer accident. Much of the cargo carried in tank cars is in some way hazardous, and it would be very handy if a drone could show the dispatcher what placard numbers* are involved so that they can coordinate cordoning off the area and possibly evacuating residents. It would also help in making sure you have the right firefighting chemicals around - lots of hazardous stuff requires foam to extinguish and reacts rather violently with good old H2O.

*If you've never read the Emergency Response Guide, you should. Some of the nasty stuff that's hurtling down the highway next to you is very dangerous and/or toxic. It's eye-opening, to say the least.

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