Dear Dave ：

Thanks for you help .

Thanks
HAO  

-----Original Message-----
From: TGAsia [mailto:[log in to unmask]] On Behalf Of David Bergman
Sent: Friday, August 19, 2011 2:37 AM
To: [log in to unmask]
Subject: Re: [TGAsia] PCB warehouse condition of temperature and humidity

Dear Hao,

The storage of PCB and materials in process for PCB is addressed in IPC-1601
Printed Board Handling and Storage guidelines.

Here is one section of the document regarding PCB storage.

5 PRINTED BOARD RECEIVING, STORAGE AND ASSEMBLY
5.1 Before Opening Dry packed packages should be inspected to verify there
are no tears, punctures, or openings of any kind that expose the contents.
If openings are found, and the HIC indicates that the dry environment of the
bag has been compromised (see 5.3), then the printed boards should be
evaluated for excessive moisture content per 5.8. Printed boards may also be
visually inspected for any changes to the final finish that may indicate
that solderability has been degraded.
If physical inspection is required, intact bags may be opened for inspection
by cutting at the top of the bag near the seal. Time of exposure to ambient
conditions should be controlled to minimize moisture uptake. If bags are
opened under factory ambient conditions (not exceeding 30 °C/60% RH), then
either:
a) Place printed boards in dry storage at 10% RH or less within one hour, or
b) Return them to dry packaging (see 4.3.1) within 30 minutes. In this case,
the original desiccant and HIC may be reused.
Note: If the 60% spot on the HIC indicates wet, the HIC and desiccant should
be replaced.
If ambient conditions of temperature, humidity, or exposure time are
exceeded, printed boards should be evaluated for excessive moisture per 5.8.

I hope this helps some.

Best regards,
Dave

David W. Bergman   大山人
Vice President, International Relations
IPC - Association Connecting Electronics Industries 3000 Lakeside Drive
Suite 309S Bannockburn, IL 60015-1249 USA
+1 847-597-2840 tel
+1 847-615-5640 fax
+1 847-867-1388 mobile
[log in to unmask]
Skype: davidbergmanipc
www.ipc.org

From: TGAsia [mailto:[log in to unmask]] On Behalf Of wuhao
Sent: Thursday, August 18, 2011 4:17 AM
To: TGAsia
Subject: [TGAsia] PCB warehouse condition of temperature and humidity

Dear all :

Does anyone can tell me if have a special standard to define the pcb
warehouse condition of temperature and humidity .
Best regards
Hao





CONFIDENTIAL NOTE: The information contained in this email is intended only for the use of the individual or entity named above and may contain information that is privileged, confidential and/or exempt from disclosure under applicable law. If the reader of this message is not the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. If you have received this message in error, please immediately notify the sender and delete the email.

Thank you. 



______________________________________________________________________
This email has been scanned by the MessageLabs Email Security System.
For more information please contact helpdesk at x2960 or [log in to unmask] 
______________________________________________________________________