[HOT] Date of a mapped feature?

[Chris Braun]

Hello,
I have experience in GIS and RS but am quite new in OSM so sorry for the 
newbie question.
Basically I would like to know if and how one can know when a feature 
was mapped on the OSM map. Or rather what was the date of the imagery 
that was used to map a specific feature. Since the OSM map is used by 
rescue teams, I would find this information quite critical to assess 
whether a feature may still exist or not, but I don't understand how 
this can be learnt from the map. There does not seem to be a systematic 
tag for the date of the image, or an automatic way to associate to a 
feature the date of the imagery that was used to map it (or the most 
recent imagery that is still showing this feature), but maybe I am 
missing something. Or maybe this can be learnt from the "history" section?

Could you kindly clarify this or point me to the relevant tutorial/resource?

Thanks a lot,
Chris