Heightened Airport Security Measures both at Shanghai Pudong and Hongqiao Airports, following impact of recent explosion incident at PVG.
You may need to schedule earlier arrival at least 3.5 hours prior to the flight for international departure and 2.5 hours for domestic departure, since new security measures are expected to increase waiting times with extra security guards stationed at terminal entrances to manually inspect.
Here is website links to read more about security check provisions by Shanghai Airport Authority in line with Civil Aviation Administration of China(english version):
http://en.shairport.com/2012-11/09/content_15901053.htm