alignment preferably each end of both themagnetic devices has electrical grounds 22 23 the brackets 31 32 are mounted so as to avoid metal to metal conductive contact between the magnetic apparatus 10 and the printing press or other equipment which is generating the static electricity on the moving web as used with a printing press the two magnetic devices 10 are so positioned by brackets 31 32 that the paper passes between them after exiting the printing press the magnetic devices 10 are preferably spaced as close as is practical say within one inch of each other so that each side of the paper must pass within say 1 2 inch of an exposed surface 25 of the magnet the length of each magnetic device 10 is preferably slightly greater than the width of the web c say a minimum one inch overlap on each end the physical proportions of each device 10 must be determined by the magnitudeof the static electricity present on the web c we know of no mathematical equation to calculate the field strength required readings of static electricity may be taken by a standard static charge meter such as model acl 400 sold under the trade name 34 static locator 34 commercially available from acl inc elk grove ill at several locations on the web c as it exits the printing press variables will affect the amount of static electricity common variables include the speed of the press the humidity in the air and the type of web material moving through the press a magnetic device 10 of strontium ferrite oxide made of available standard sized 1 u00d7 2 u00d7 6 inch blocks 17 having nominal properties of residual induction 390 m tesla commercially available from crucible magnetics corp elizabethtown kty as ferrimag u00ae.