Olefin (polypropelene) represents between 35 and 40% of all commercial carpet installations. (Nylon accounts for about 60%). Olefin is often made as a
looped carpet, like a Berber. It absorbs oil more
easily than nylon, and oil is difficult to remove
from olefin. It also loses its resiliency quickly
(tends to flatten and to resist coming back up,) even
after only a few to several months on the job.
Its plastic finish scratches easily, causing light to
be reflected in a diffuse manner, causing it to appear
as soiled even when it is clean. Hope this helps.