From: Teddy Ruxpin
Subject: FL: Electromagnetic fields, fursuit animatronics, and the human body
From: A list member
Recently, in my Circuits class, my instructor explained to the class how power
sources developed electromagnetic fields, and, though he explained that the
theories were still rather controversial, he noted that these electromagnetic
fields could have an effect, most possibly harmful, on living organisms,
including the human body.
This is mostly rubbish. Any present technology we have involving simple magnetic field generation is incapable of producing a field that will do anything other than _heat_ body tissue. It has been demonstrated that the human body is not ferromagnetic, and is therefore unaffected by the 'magnetic' field.
Here is a list of risky things associated with electronics, and living in our present society: (and for the nit-pickers, sure this glosses over the details, but I don't want to bore you too much :)
1. Parts overheating and burning you, or other things that may produce noxious fumes. Install fuses or 'polyswitches'. Design well. Insulate.
2. High voltage giving you a shock. Use low voltage ( <48V ) and insulate. Note that breaking the current through a lare inductor (coil - as maybe in a relay) can produce a large 'back-emf' which can give you a surprising momentary shock, even when the primary voltage is only a few volts.
3. High power, high frequency RF. (Not exactly likely in a fursuit, is it?) I'm talking like Microwave ovens and radar transmitters here. 2GHz or greater and at least several watts to start being a hazard - though it really depends on energy density and the nature of what its applied to. Cell phones at 900Mhz and 250mW don't hack it. 200W at 14MHz doesnt either (I know - been there, done that). 600W 2.5GHz microwave ovens are a problem - - hence all the interlock switches. 50kW of 700MHz TV transmitter signal will warm you up good too - thats one reason why the antennas are way-off the ground. BUT - all the effect these have is to heat you up. If you dont get cooked for too long, the effect is much like being baked. Yes, there's exceptions which are sensitive - those body parts that are poorly cooled - eyeballs, and certain parts of the male anatomy.
4. Things that produce 'Ionizing Radiation' can and do damage living tissue. Ionizing means it can rip electrons off molecules, making them more reactive - - and somtimes they then combine with things they should not, and become changed. So what is ionizing radiation? Put simply it is Ultra-violet and higer frequency electromagnetic signals. (Visible light, infra-red, heat, microwave, radio waves .. all have lower frequencies and are non-ionizing.)
The number 1 danger - THE SUN. Stay in the shade or wear sunscreen! This stuff damages skin. Way more dangerous than a cell phone - unless you poke yourself in the eye with the antenna.
Other ionizing sources - Cathode Ray Tubes - yes, the monitor you are probably looking at! It's an electron particle accelerator, but the tiny amount of ionizing radiation it produces when the beam hits the screen is stopped by that thick glass they put in the screen. X-Ray Machines - you know how careful they are with them. Radio-Active Material - same again (mostly). Big Particle Accelerators - again, lots of safty measures. Cosmic Rays - say what? These are at the top end of the energy range. They are produced by stars and are such high energy they mostly go right through everything. Theres about 400/second/square meter on earth's surface. We have been living with them for millions of years, so don't start worrying about them now :)
So in summary - watch out for #1 and #2 with your suit electronics. Take it easy on the sun-tan, and don't mess with the apppliances! (I'm not talking prosthesies.)
From: Christopher John Thomas
Subject: Re: FL: Electromagnetic fields, fursuit animatronics, and the human body
A list member wrote:
For fursuits with animatronic parts – especially for the head – could the
power sources for the animatronics develop electromagnetic fields that could
possibly be a slow health hazard?
Extremely unlikely, for several reasons:
- Most fursuit electronics operate at far, far lower frequency. Inductive and capacitive coupling to the universe are proportional to frequency, so your radiative emission will be a few million times less intense for fursuit electornics than for your 1.x GHz cell phone.
- Cell phones are _designed_ to emit radiation (they're radio/microwave transcievers). Most fursuit electronics isn't designed to, and so will radiate far less (only radiation will be from parasitic inductance and capacitance to the rest of the universe).
- IMNSHO, the claims of cell phones causing harm are bogus. If there was a substantial effect, it would be a lot more noticeable. What's actually happening is that measurement noise in the studies is “suggesting” things, and the public is glomming on to it like crazy (it uses “radiation”, so it *must* be bad! Aaah!).
Summary: If I was putting electronics in a fursuit, I'd be worrying about fire hazards, not radiation hazards.
From: MoonShadow
Subject: Re: FL: Fiber Optic/EL Resources
Oh, excellent post, I like this one… :)
Several 'List members have asked for more information on
electroluminescent technology and fiber optic resources.
My current list of stuff follows, but first, something extremely
important:
A SAFETY WARNING AND DISCLAIMER:
Several members have mentioned safety/health issues with
optical fibers. It also bears mentioning safety about ANY use of
electricity in a Fursuit.
First: NEVER, EVER USE GLASS FIBERS!
USE ONLY *PLASTIC* OPTICAL FIBERS IF YOU WANT TO ATTEMPT/EXPERIMENT
WITH ANY OF THIS!
Some one mentioned using fishing line. It's cheaper and easier to handle. And I am sure that there may be an uncle in the family that would not mind sparing a couple of feet of his fishing line. This is what I am going to do.
Moonshadow is right!
Ordinary GLASS optic fibers are TOO DANGEROUS TO USE!
They break very easily and WILL get under you skin! Image if
you have them stuck in your fingertips and then rub your eyes!
We're talking a quick trip to the emergency room! :(
USE PLASTIC FIBERS ONLY! They're softer, cheaper, and don't
break or splinter.
Well, you can take a trip to the emergancy room, but, I don't think that it would do much good, but, if you don't mind fileting an eye to find a little sliver of glass go ahead.
The thing about glass and plastic optical fiber splinters are: They DO NOT show up on x-rays.
Wood shows up and can be seen and extracted from the skin, or they are absorbed into the bloodstreem. You need more fiber in your diet anyway…
Metal shows up bright white in X-rays, these can be easily spotted and removed.
Plastic and glass fiber optic disappear. Both under the skin and thru X-rays.
Secondly: BE CAREFUL WITH ELECTRICITY, ESPECIALLY HIGH VOLTAGES!
Electroluminescent lamps work on high voltage, high frequency
alternating current, make sure ALL parts and connections are
properly insulated. (Every manufacturer is different, but I've
seen power spec ranging from about 100 to 260 volts, frequency
from 60 to 1000hz, but all current ratings were in the low
milliamp per square/cm range).
I agree, but, to see something in the 1kHz range, I don't think that I have seen this unless it's in the radio controled area. But, the voltages are valid.
I've zapped myself a couple of times from the little EL power units
I have at home and they have an unpleasant sting, but not much else.
Lucky!
Still, ALWAYS be careful and design your projects for maximum
safety, for your sake and for your audience's.
I usually make mine on a bread board before I put them into something perminant. Like a card or circuit board. But, it's been a while.
Strobes are a different story.
A shock from a strobe can knock you to the floor or KILL YOU
OUTRIGHT! I'm NOT kidding. I've accidentally touched a home-built
uninsulated strobe unit and got a hellova shock, even though it
was only battery-powered!
You are VERY lucky.
Also remember strobe CAPACITORS HOLD A POWERFUL CHANGE EVEN WHEN
TURNED OFF!
High voltage capacistors(spelling) are made to hold more than 100 volts (or more) at a time. When they discharge their voltage, they discharge it immediatly in one burst. This is enough amperage to kill you. After all, you can be killed at about 1/2 amp of current.
When servicing/handling them exercise EXTREME caution!
Enclose ALL electronics in appropriate dielectric containers and
insulate all connections thoroughly.
Again, use a bread board.
USE COMMON SENSE - IF YOU DON'T KNOW WHAT YOUR DOING, FIND OUT
HOW OR DON'T DO IT! ! !
Training is something that I reccommend going thru. Or some one that knows what they are doing.
-High intensity incandescent bulbs can get hot enough to blister skin
IN SECONDS. Enclose the bulbs so no one, 'suiter or spectator, can come
in contact with them. Better still, use low voltage, cool LEDS instead.
Incandescent bulb filiments can reach up to and including 1200F Degrees. There are talks of the DOT in New York (I think) that are going to replace the incandescent bulbs of the tail lights of public transportation busses with clusters of LED's. This will be a little more expensive, but, they will last longer, burn brighter and offset the cost of replacing the bulbs.
-ALWAYS have a main safety FUSE in your 'suit circuitry. Even a NiCad
power-pak can dump enough power to burn you BAD if it gets
short-circuited. Batteries can leak or burst too, if shorted.
POP! And even though there is only 6-9v in these things, there can be something that can and will burn you. A short Circuit can set fire to anything, and make the battery leak, and possibly explode.
-Take appropriated safety measures when working with ANYTHING
TOXIC. (Its been said before - I'm sayin it again)
Preach on…
DISCLAIMER: All information supplied in ANY of my posts or Emails
is supplied “AS IS”. It WILL obviously contain errors as this is
an experiment; I'm learning this as I go along. It also means
YOU USE THIS INFORMATION ENTIRELY AT YOUR OWN RISK. I bear no
responsibility or liability WHATSOEVER for any loss, injury,
damage or liability you may suffer using any part of it.
This is a good call, and an excellent measure.
Sorry, I don't mean to sound “gruff” but I have to be
perfectly clear on any potential hazards.
S'alright.