CRT handling Was: Re: It's ALIVE!

Christian Fandt <cfandt(a)netsync.net> wrote: Hi The number I remember was 20-50mA. There are two ways to kill one self. One is to cause the heart to convulse and the other is to burn the tissue. To cause the heart to convulse takes a smaller amount of current but the heart will usually restart when removed from the current. This is why high DC is more dangerous than AC. With DC, your muscles tend to lock, holding onto the hot wire. This keeps the heart locked up also. With low frequency AC, it tends to make the muscles jerk. This usually separates one from the hot wire. In all of these cases, so far, at most, artificial respiration will bring one back. In the next realm is the higher currents that actually burn the heart tissue. You rarely recover from this. Now on to RF. Even though there may be a high enough current, most only suffer surface skin damage. This is because of the fact that the current in RF tends to flow mostly on the surface because fast change in directions of current also require that the magnetic field associated with it be able to change as well. Changing magnetic fields create eddy currents in conductors that limit the rate that they can penetrate that conductor. This is called the "Skin Effect". What it means is that for RF or short pulse DC ( such as lightning ) the current tends to stay on the surface of your body and not effect the internal parts as much. This is why some live through lightning strikes but the guy working on the washing machine is dead. While working around CRT's the high voltage anode is a problem. It will not usually kill one but it will make you uncontrollably jump. Where your hand and arm go, may be through the back of the tube. This is usually a bloody experience. Dwight