I forgot to add this one: there is another reason for being careful with even lowest charges, namely the fact that many devices may not get ESD damaged, but they can change electrical status, which can be problem enough! The following is just one of many such examples. Inge "Today's TTL and CMOS logic states have a logic "0" at 0.8 Volts or lower and a logic "1" at 2.0 Volts or higher. This leads to a smaller indeterminate range of 1.2 Volts for most TTL and some CMOS logic circuits and places the logic inputs from these circuit traces or cable connections susceptible to induced EMI voltages exceeding this range. One example of an ESD-induced EMI was characterized from office chairs [3, 4]. Induced voltages over 2 Volts have been measured on a printed circuit assembly (PCA) 90 cm from the furniture ESD [4]. Two Volts is enough voltage to easily drive a TTL circuit let alone an ECL circuit into a logic error. " From ESD Journal. -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Roger Stoops Sent: den 5 mars 2007 15:22 To: [log in to unmask] Subject: Re: [TN] ESD question Like the old saying, 28 grams of prevention is worth 454 grams of cure ! -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Hernefjord Ingemar Sent: Monday, March 05, 2007 9:18 AM To: [log in to unmask] Subject: Re: [TN] ESD question There are no paragraphs for that obvious and given case: of course anyone MUST use heel straps! The one who says he will not touch anything, one minute after gave this promise, he may be charged to several Volts or even hundreds Volts (if he hasn't ESD shoes) and after two minutes he may have forgotten not to touch anything. Ask some guys to walk around and then place their feet on the ESD tester, and you'll probably have proof enough. 10 VDC discharge at 10 picoseconds is enough to cause damage to certain 1.5 V devices! Inge -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Bob Arciolla Sent: den 5 mars 2007 14:57 To: [log in to unmask] Subject: [TN] ESD question Good Morning all, A question regarding ESD has come up in our facility. Our SMT area has ESD flooring and the question that came up is that one of our instructors says that anyone entering the room must have heel straps on and another says that if a person is just going into the room and not touching product, they don't need heel straps. Who is correct? Regards, Bob Arciolla Endicott Research Group Quality/Safety Manager 607 754-9187 ex 3034 607 754-9255 fax cell 607 624-8516 --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------