UER Store order your copy of Access All Areas today! Activity 911 online Server Time: 2024-05-13 20:03:22 Visit Infiltration Access All Areas AvBrand

1 2   UER Forum > Archived UE Tutorials, Lessons, and Useful Info > Radio Frequency Fields? Dangers? (Viewed 1429 times) ursusarctos   |  Radio Frequency Fields? Dangers? < on 3/13/2004 10:28 AM >   Hi all-- Recently, I've been exploring a nice old hospital (still in use) in Chicago, Illinois. I've found an unlocked entry to one of the building's spectacular towers. But at the base of the ladder up to it, there's a sign warning that "Radio Field Levels may exceed FCC guidelines for safe exposure," or something to that effect. (Sorry, I'm not digital camera equipped, otherwise I'd attach a photo....) Looking up at the tower from the outside, it appears that it hosts a nice array of antennas and such. So I'm wondering, how seriously should I take this warning. I'd like for my children not to have severe birth defects, but the tower just needs to be accessed. Should I treat the sign as a strongly worded version of "do not go beyond this point if you have a pacemaker," or is this something more serious? Thanks! Uncle Goose  Location: Ghent, Belgium Gender: Male The Goose knows best.  |  |  Re: Radio Frequency Fields? Dangers? <Reply # 1 on 3/13/2004 11:21 AM >   I don't think you will experience any effect if you do this once, it's more like if you would live near it or being in the neighbourhood a lot that it's a higher risk. Smoking 1 sigaret wouldn't kill you but 20 years can. A 1000 days of sorrow can disapear in a split second, it takes only one person to make it happen. Rockman1  Noble Donor Location: Depends on the time of day Gender: Male  |  Re: Radio Frequency Fields? Dangers? <Reply # 2 on 3/13/2004 2:33 PM >   From what I have been told, even brief expoaure to one of these arrays can fry you. It depends on what frequency is used and power output, perhaps somebody with more experience can elaborate more. Gettin' close to an overload...everyday's a no win situation.. PAWolf  Not from Pennsylvania Location: KCMO Gender: Male We haven't located us yet.  |  |  |  |  Re: Radio Frequency Fields? Dangers? <Reply # 3 on 3/13/2004 4:17 PM >   I've read that if you get to close to live transmitter antennas that they can arc to you and give you really severe RF burns. I'd listen to the signs. Make Beer, Not War. MacGyver  Location: St Paul, Minnesota Gender: Male "Someone go find me a paperclip, a D-cell battery, and a cheese grater"  |  Re: Radio Frequency Fields? Dangers? <Reply # 4 on 3/13/2004 6:40 PM >   If there's a ladder, then there is probably a "safe" way for workers to get on the roof. I'd scope it out from a distance if possible, and see if you can tell what kind of antennas are where. From the little I know about this kind of stuff, some of the potentially more dangerous antennas are the ones that look like a large drum. These are transmitters, and oftem times use microwave frequencies. Ever heard of what happens when a live critter ends up in a microwave? I'd advise giving any drum antennas a wide conical-shaped berth. Pointy stick antennas are most likely either receiving antennas or some kind of omnidirectional transmitter, which may or may not be powerful enough to hurt you. There was some brief discussion of this very topic some time ago. http://www.uer.ca/forum_showthread_archive.asp?&threadid=1059&currpage=1&pp#post11 Like a fiend with his dope / a drunkard his wine / a man will have lust for the lure of the mine "If you are not part of the solution, you are not dissolved in the solvent." nostra-YOUPPI!  Umpire Location: Shahre:'on Kaybec Bonsoir et cest partie  |  Re: Radio Frequency Fields? Dangers? <Reply # 5 on 3/13/2004 7:27 PM >   i just know for a fact that AM transmitters are very dangerous cus the antenna is the tower!!! you got to stay away from em!! Montreal Expos 1969-2004 Forever Proud Lets Keep The Dream Alive Arrow  Noble Donor Location: Minneapolis Gender: Male  |  Re: Radio Frequency Fields? Dangers? <Reply # 6 on 3/14/2004 5:19 AM >   Posted by exposfan i just know for a fact that AM transmitters are very dangerous cus the antenna is the tower!!! you got to stay away from em!! Precisely right with the AM towers. You can't touch the ground and the tower at the same time. Here's one of those drum type antennas: http://www.gordon.army.mil/AC/spring02/towrclim.jpg Another type: http://www.qsl.net/kf4lhp/telweb/microwave/kia53/roundhorn.jpg Some safety info: Radio frequency transmitters can cause heating in tissues... (From http://www.fcc.gov/oet/rfsafety/rf-faqs.html) Two areas of the body, the eyes and the testes, are particularly vulnerable to RF heating because of the relative lack of available blood flow to dissipate the excessive heat load. A good warning to take seriously. Edit: Links to images instead of including...total size ~200K. [last edit 3/14/2004 5:20 AM by Arrow - edited 1 times] Mousey  This member has been banned Location: UK Gender: Male Shugah! (aspartame kills)  |  Re: Radio Frequency Fields? Dangers? <Reply # 7 on 3/14/2004 5:16 PM >   Radio Frequency radiation warnings are placed a safe distance from transmitters that can cause permanent health complications. There are many differing views on the subject, but the prevailing one is that if they don't fry you alive, they will enduce cancer in some form or another. The affects aren't instant, but rather develop over time. I personally wouldn't even go near such a device unless I was certain it was off. If a company put one near my home, I would petition for its removal. No, I would vandalise it beyond use - how dare they put one there without my consent. I refuse to live near such equipment. Be it cell phone relays, TV and radio boosters, or simple antenna. That's just me though. I strongly disagree with any technology unless it has the green light from every health expert researching the subject. [last edit 3/14/2004 5:17 PM by Mousey - edited 1 times] In Soviet Russia, forum flame you! kc  Noble Donor Location: Pueblo, Colorado Gender: Male "yah, im hangin the drywall at the new Mc. Donalds"  |  |  Re: Radio Frequency Fields? Dangers? <Reply # 8 on 3/14/2004 7:17 PM >   im an amateur radio operator, and i know at least the antenna and frequencies we use can burn you if you touch the antenna while it is transmitting, and as for AM towers i agree with whats been said above..touch it and you wont like it. Doing a job RIGHT the first time gets the job done. Doing the job WRONG fourteen times gives you job security. Mickael  Moderator Location: Canada Gender: Male  |  Re: Radio Frequency Fields? Dangers? <Reply # 9 on 3/14/2004 11:29 PM >   Are those two things Microwave antenna ? I didn't tried to put my hands in front of them Need forum-related help / Besoin d'aide reliée au forum ? Contact a moderator MacGyver  Location: St Paul, Minnesota Gender: Male "Someone go find me a paperclip, a D-cell battery, and a cheese grater"  |  Re: Radio Frequency Fields? Dangers? <Reply # 10 on 3/14/2004 11:44 PM >   Posted by w00t Are those two things Microwave antenna ? They remind me of cellular phone network repeaters. So maybe. Like a fiend with his dope / a drunkard his wine / a man will have lust for the lure of the mine "If you are not part of the solution, you are not dissolved in the solvent." scourge  Location: United States Gender: Male strive  |  Re: Radio Frequency Fields? Dangers? <Reply # 11 on 3/15/2004 12:14 AM >   Some notes. I posted this in the old thread, but it apparently no longer exists. RF can burn you or give you cataracts (or as said, cause testicular damage) but its damage is limited to cooking you. Same with microwaves. Contrary to popular belief, neither RF nor microwaves can give you cancer. Only ionizing radiation can cause cancer, the lowest frequency of which is ultraviolet light (causes skin cancer). It does not matter the magnitude of the signal, only the frequency. Thus a single X-ray photon potentially could cause genetic damage, whereas a 70 kilowatt FM broadcast transmitter never will (though it will burn you badly if you come close). This is not to say that RF emitters are harmless. RF burns cook your flesh inside and out rather evenly, so unlike a conventional burn that only damages the skin, an RF burn penetrates deep into muscle tissue and is therefore very painful until it heals. Also, understand that to put out the amount of power that broadcast stations do (several kW for AM, dozens of kW for FM) there have to be plenty of amps coursing through that antenna, and very high voltages are present. If you get close enough to an antenna to touch one, not only will you get cooked, you could be electrocuted. The further you are from an antenna the safer you are. This relationship is geometric. For an isotropic (omnidirectional, think of a round, point-source light bulb) radiator, the field strength decreases as a function of the inverse square of the distance from the emitter. Thus spending 4 minutes 4 feet away from the antenna will give the same RF dose as spending 1 minute 2 feet away from the antenna. (Or 15 seconds 1 foot from the antenna). Of course an isotropic radiator is theoretical, and most antennas are directional in some way or another, but the commonest ones used for broadcast (usually verticals) have a relatively isotropic radiation pattern all around. This is logical, because they want the broadcast signal to reach listeners in all directions. Fixed antennas used for communication may or may not be more hazardous. The drum-looking ones, as well as dish antennas or beam (yagi, etc) type antennas are very directional and focus their radiation pattern in one or more narrow lobes, in which the RF energy stays strong and focused for a much farther distance than that from an isotropic radiator. These are the ones to stay away from. You may think that they project RF energy only in the direction they face, but most such antennas have back lobes or side lobes where the field strength is very high. You won't necessarily know where these lobes are. The bottom line: Wherever you see RF warning signs, tread cautiously. If antennas are present but there are no warnings, use good judgement. Edit: Emphasis [last edit 3/15/2004 3:47 AM by scourge - edited 1 times] sierra hotel Mousey  This member has been banned Location: UK Gender: Male Shugah! (aspartame kills)  |  Re: Radio Frequency Fields? Dangers? <Reply # 12 on 3/15/2004 6:46 AM >   Look at a microwave oven for instance. There are certain sides to this argument of whether RF and microwave cook you or cause cancer. There is the one side that says it just cooks, and there is the other side that says it does both. I'd rather not risk it. I don't know enough to feel safe with what the 'experts' suggest. But what I do know, is that incidence rates of those cancers on which attention has been focussed have not changed much in the last 50 years (some have actually decreased), even though the use of RF radiation has increased in our society. So there is evidence to suggest that they are safe. In Soviet Russia, forum flame you! nostra-YOUPPI!  Umpire Location: Shahre:'on Kaybec Bonsoir et cest partie  |  Re: Radio Frequency Fields? Dangers? <Reply # 13 on 3/15/2004 3:01 PM >   whats cool with AM sites is the placement of the towers can direct the signal, one am station has 8 towers in two rows that form a 2 mile alleythat fires a 50 000 watt signal down a street in houston Montreal Expos 1969-2004 Forever Proud Lets Keep The Dream Alive HAMMERTIME  Location: Reading Pennsylvania Gender: Male mmm, a box . . . just a box  |  Re: Radio Frequency Fields? Dangers? <Reply # 14 on 3/26/2004 8:57 AM >   What about using an E.M.F. detector or radar detector (with microwave sensing ability) to check if the antenna have power? I bought an E.M.F. detector for about $20 from a department store. It's supposed to check for high levels of electro magnetic fields near your computer, high tension wires, near the microwave, etc. Just a thought, I really don't know that much about towers but am sure glad that I've been reading these posts. I had never heard about AM tower = death / pain before and I love to climb. I'm sure though that these towers have warning signs. Chronic  Very Noble Donor Location: Kitchener, ON Gender: Male Architecture has only two enemies. Water and stupid men.  |  Re: Radio Frequency Fields? Dangers? <Reply # 15 on 4/22/2004 11:12 PM >   RF exposure causes headaches at the worst for minimal exposure. Safety Code 6 here in Canada stipulates that antennas must be mounted in such a way on structures or rooftops so that persons cannot walk or stand in front of them. When my crews work on a live broadcast tower the client must turn down the power to acceptable human exposure limits as outlined by OHSA. Long "whip" antennas are omnidirectional and radiate RF in a circular pattern. Panel type antennas are directional and radiate the RF out in front, in beamwidths up to 90 degrees. The round "dish" antennas are transmitting microwave RF out in front of them. Avoid microwave RF exposure if you have to avoid anything. Headaches, sore neck, nausea, and even sterilization can occur. Yes, the AM towers are "hot" and if you do get on one, jump onto it without having one foot on the ground and one foot or hand on the tower. The other obvious dangers of UE'ing a tower is the fall potential. Get a clinbing belt and a trolley or rope grab that fits the safety rail or cable. Anyone that does not use one and dies or gets hurt, deserves it. 01:14:16] <Chronic> Conrad...ya gotta go.... [01:14:30] <nightbird> yes Mr. Black, life is funnier than a pocket full of stocks! And...Tim has legal friends in Chicago...we'll get thru this!!! lago1  Location: the 'Go  |  |  Re: Radio Frequency Fields? Dangers? <Reply # 16 on 4/29/2004 2:10 AM >   Could you please hint at what hospital? I'm also a Chicagoan, just interested... null_recipe  Location: Portland, Oregon Gender: Male  |  Re: Radio Frequency Fields? Dangers? <Reply # 17 on 5/3/2004 9:52 AM >   Additionally RF can literally cook you and it can have delayed symptoms depending on the power levels and exposure time. When I was in the Navy I heard about an incident which killed 3 (or 4) people. In one of the Radar transmitter shops someone forgot to hook up a "dummy load" (A device to cap and and absorb the energy.) They then tested an F-14 Tomcat transmitter anywhere from 15 to 30 minutes. A few hours later every tech went to the base hospital for not feeling well and they died before the day was out. With a transmitter tower I would not go anywhere past any of the warning areas. You cannot assume they are not being used unless you are the one shutting them down and putting a pad lock on the power lever. A cheap and eaasy way to check for high levels of RF radiation is to take a small flouresent bulb with you and it will light up. I was told that back in the old days techs used to check for RF transmission this way on A-7 jets. Since I have never done this myself to verify it works, I personally would opt for a portable signal power meter and I do not advise using the bulb method unless as a last resort. Conundrum  Criticón Location: GTA Gender: Male Now Entering The Bling Chamber  |  Re: Radio Frequency Fields? Dangers? <Reply # 18 on 5/3/2004 2:44 PM >   Posted by kc im an amateur radio operator, and i know at least the antenna and frequencies we use can burn you if you touch the antenna while it is transmitting, and as for AM towers i agree with whats been said above..touch it and you wont like it. NZero showed me how powerful radios, and antennas are first hand, he had a handheld radio, and proceded to give me a nice radiation burn on my finger, and gave some other people burns on their legs through their pants, all by removing the antenna, putting the port on the radio close to the skin and pushing the talk button. It hurt like a *****. Conundrum [last edit 5/3/2004 2:45 PM by Conundrum - edited 1 times] This posting is provided "AS IS" with no warranties, and confers no rights. Carpe Noctem Mancubus   |  Re: Radio Frequency Fields? Dangers? <Reply # 19 on 5/3/2004 3:01 PM >   My dad has worked in radio for a long time. I've been down to transmitter sites to work before, and nothing has happened to him or me. Although he told me about one time he was on a tower and he said it was getting really warm from the microwave field. I guess maybe I've been seeing those signs for such a long time they've lost meaning to me. Heh. UER Forum > Archived UE Tutorials, Lessons, and Useful Info > Radio Frequency Fields? Dangers? (Viewed 1429 times) 1 2   All content and images copyright © 2002-2024 UER.CA and respective creators. Graphical Design by Crossfire. To contact webmaster, or click to email with problems or other questions about this site: UER CONTACT View Terms of Service | View Privacy Policy | Server colocation provided by Beanfield This page was generated for you in 156 milliseconds. Since June 23, 2002, a total of 741594759 pages have been generated.