---- Begin Forwarded Message Return-Path: <[log in to unmask]> Received: from simon.ipc.org (IPC.ORG [168.113.24.64]) by ixmail6.ix.netcom.com (8.7.5/SMI-4.1/Netcom) id HAA07337; Wed, 4 Dec 1996 07:06:14 -0800 (PST) Received: from ipc.org by simon.ipc.org via SMTP (940816.SGI.8.6.9/940406.SGI) id IAA14925; Wed, 4 Dec 1996 08:58:32 -0800 Resent-Date: Wed, 4 Dec 1996 08:58:32 -0800 Received: by ipc.org (Smail3.1.28.1 #2) id m0vVHWz-0000YVC; Wed, 4 Dec 96 07:38 CST Resent-Sender: [log in to unmask] Old-Return-Path: <simon.ipc.org!nicmad.nicolet.com!nicmad.nicolet.com!mcguine> Old-X-Envelope-To: [log in to unmask] Message-Id: <[log in to unmask]> X-Sender: [log in to unmask] X-Mailer: Windows Eudora Pro Version 2.2 (16) Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Wed, 04 Dec 1996 07:10:33 -0600 To: [log in to unmask] From: Pat McGuine <[log in to unmask]> Subject: GEN: Acceptable level of indor humidity? Resent-Message-ID: <"ad8lK1.0.1JH.FxNfo"@ipc> Resent-From: [log in to unmask] X-Mailing-List: <[log in to unmask]> archive/latest/8227 X-Loop: [log in to unmask] Precedence: list Resent-Sender: [log in to unmask] Status: RO Hello All: Could anyone please advise as to what the acceptable range of indoor humidity for a electronics assembly facility is? Also, what methods have been successful in boosting the humidity level during the winter months - can you put me in touch w/ a contractor who has installed humidity increasing equipment in your facility. -Pat- ------------- Patrick McGuine Nicolet Instrument [log in to unmask] (608) 276-6334 Pat, There are several factors one should consider regarding rH in your facility. One factor worth mention is ESD. To the best of my recollection, 40%rH is the lower end one might desire to minimize inadvertent static generation. On the other end of the spectrum, increased rH will accelerate solderable surface oxidation and substrate absorption, a reasonable upper limit might be 60%rH. Therefore, 50% +- 10% would be a good starting point. I do not know of any formal studies done on this and the data above is strictly "bits and pieces" from various trade sessions, conferences and seminars. Another issue is HVAC efficiency and creature comforts. This is pretty clearly discussed in the book : "Industrial Ventilation" by: Commitee of Industrial Ventilation P.O. Box 16153 Lansing Michigan, 48901 (513) 661-7881 Library of Congress Catalog Card No. 62-12929 I would suggest that you contact your local HVAC service organization who has working knowledge of your facility heating and cooling systems. Most likely they can be helpful in choosing the best humidity control system for your building's specifics. A word of caution: as one attempts to "economize" by heating outside air and recirculating the warm inside air thereby reducing makeup, the differential barometric pressure of the building will tend to fall as you begin "starving" the exhaust systems in your soldering/cleaning/etc. equipment. Be sure to evaluate the proper make up air as you explore the solutions to this challenge. Regards, Edward J. Popielarski QTA Machine (714) 364-6614 [log in to unmask] ************************************************************************ *** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * ************************************************************************ *** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * ************************************************************************ *** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * ************************************************************************ *** *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * *************************************************************************** * If you are having a problem with the IPC TechNet forum please contact * * Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask] * ***************************************************************************