I have never seen a temperature or chlorine limit when I purchased my covers, but if they are the limits you say, then it is no wonder mine never last! We hae a salt water chlorine system, but we still periodically shock it with a packet of shock. That probably violates the 1ppm limit. We also get temps of greater than 100 degrees in our water during the summer! I will literally take the cover off, and just add water to let evaporation do its thing to keep it that cool... ;-)
Charlie