When I have completed FDA validations of wave soldering I accomplished acceptable profiles to the most delicate component on the board. In general most caps/resistors could withstand 235C for 1-5 seconds. Inductors were always a lot lower but very dependent on the material used. I would take the bill of material and go to each component manufacturer and request maximum temp/time information.

Wouldn't the ability to do thermal damage to components be a function of the dwell time in the heat source... there is a time factor, isn't there, that affects the equation? If components can have their leads raised to 500+ F for normal SN63 soldering without damage..then there must be a similar technique involved..

I believe the operator sets up a profile that soaks the assembly up to a given temp and then spikes the temperature to reflow temp for a few seconds as it passes that point in the oven... then it is immediately reduced in temp before the part bodies can actually absorb enough heat to raise the internal temperature high enough to do them damage.... I don't have all the details, I am just a PCB Designer... but I think that's how it's done... so setting a general limit would be impossible because there are more variations due to design and component location, and heat sinking, and thermal conductivity of the components and their susceptibility to thermal damage... I would guess your limit to be the most easily damaged part on the board... rather than an arbitrary general temp limit... Perhaps there is some more to it than I know, though...