I understand that this type of test is appropriate for benchmark evaluation of a cleaning process. The actual value given from a test does not tell you that the boards are clean. The test results tell you if a process has changed. As I recall 9 micrograms/sqcm is Bellcore and 23 is the MIL number. It is important to remember that the result is an average of contamination across the entire assembly. There may be local concentrations of contamination that are unacceptable. Were you looking for a copy of an owners manual a while back? Contact me I can get you a copy. Omega meter Question Date: Tue, 31 Aug 1999 14:14:58 -0700 From: "Davis, Mary M." <[log in to unmask]> My apologies if this question is a repeat. I sent it once but did not see it posted or see any response so I am trying again. I have run across an internal specification which applies an equivalency factor to the maximum allowable limit for an Omegameter 300 and an Omegameter 600 - but NOT to the maximum allowable limit for an Omegameter 500. In other words, the maximum permissible micrograms NaCl eq./sq.cm. for the Omegameter 500 is less than that for the Omegameter 300 and Omegameter 600. Can anyone explain the logic for this? Is the Omegameter 500 different? Thanks in advance for your help. Mary M. Davis Eldec 425-743-8327 ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ##############################################################