In a message dated 10/23/2000 7:02:13 AM US Eastern Standard Time, [log in to unmask] writes: > Hi TechNetters, > I need some help regarding Cleanliness. Now I have an automatical test > machine whose name is omega 600. I usually test 10 minutes for cleanliness of > PCB. Can anyone give me the best advice about the test time of omega 600 > machine which is used in PCB and tell me the cause ? The 10 minute test is the one that has been in historical military specs for ages. No one tests longer than this because the numbers just keep going up. Sometimes from leaching of the product, sometimes from carbon dioxide mixing from the air. If you want to know more about these instruments and their general shortcomings, you should read EMPFs report RR00013, "An In-Depth Look at Ionic Cleanliness Testing". You can get it at EMPF.org or the IPC is working on making that available as an IPC technical paper. Doug Pauls CSL --------------------------------------------------------------------------------- TechNet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF TECHNET Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------