Hi Tony: Positive Air pressure is maintained by the AC make up air. Usually, 10 to 20% of the air in the building should be from outside air, so the AC intake forces air from outside and created positive pressure in the building. Yes internal doors can be kept open, but outside doors should be kept closed. One way to check if there is positive air pressure is to stand by a cracked outside door and feel breeze of air going out. Positive air pressure prevents fumes from accumulating to dangerous levels. If the AC is not hooked up that way, a blower should be installed on an outside wall to bring outside air in and do the same thing. Regards, Ramon -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Kevin Glidden Sent: Tuesday, March 07, 2006 4:34 PM To: [log in to unmask] Subject: Re: [TN] Positive Pressure Hi Tony, I can't answer your question about controls to maintain positive pressure, but I can point out to you that this is not a REQUIREMENT of J-STD-001. It is a RECOMMENDATION. The key word in the spec is "should": "3.6.1 Environmental Controls The soldering facility should be enclosed, temperature and humidity controlled,and maintained at a positive pressure." Only the word "Shall" makes a binding requirement. See section 1.4: "1.4 Definition of Requirements. The word shall is used throughout this document whenever a requirement is intended to express a provision that is binding." I went through this same thing for a customer audit to J-STD-001. Our facility had AC, but the humidity was not 100% controlled, and we did not maintain positive pressure. They insisted the facility had to meet all the items listed in 3.6.1, but that is not the case. I would say that if your investigation yields it would take significant investment to bring your facility in compliance with section 3.6.1, then you at least have a leg to stand on in stating it is not required per the specification. Good luck, Kevin -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Tony Gasso Sent: Tuesday, March 07, 2006 3:56 PM To: [log in to unmask] Subject: [TN] Positive Pressure Recently a customer has requested we comply to paragraph 3.6.1 to maintain positive presure in our facility during soldering operations, for terminals, wire preping, limited radial components and PCBA's per J-STD-001C We have an open assemlby area of about 10,000 Sq. Ft., lowered 12' drop ceilings, and AC but internal doors remain open to both the fabrication area as well as to the parking lots outside. Other than placing chart recorders to monitor pressure, temp. and himidity, does anyone else have similar problems with maintaining environmental controls in your facility and have you had any positive results with your controls? --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e 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 1.8e 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 1.8e 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 -----------------------------------------------------