How is the lifespan of dyneema slings when stored indoors (not used). I have some that i have not used in a long time (maybe 5 years old used 3 or 4 times) and am wondering if they degrade enough in storage that i should consider them suspect.

i have read how they degrade somethign close to 50% strength in 3 years. is that even if they are not in use?

i dont think so- dyneema mostly degrades with loading and UV exposure.

i'd call Mammut US and ask- my guess is they'll say 5 years total life span.

i would use them without question....but that's just me

AFAIK that 50% in 3 years figure came from the testing Joe Healy has done on his heavily used Mammut slings. I have tested a single Mammut sling, VERY LIGHTLY used for about 6 years and it was IIRC about 80% of rated strength. So I feel, as others do, that it's not time but rather use that wears these skinny slings out.

Dyneema isn't milk.