Can someone in Technetland tell me how the acceleration factor of 1 week at 85C/85% RH equivalence to 1 year of tropical service was derived? Also, what is the acceleration factor for the Class 2, 50 C, 80% RH conditions? Does anyone have a method for calculating acceleration factors for conditions that deviate from those above? Thanks. Marianne Romansky, Process Development, Celestica [log in to unmask] ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ##############################################################