There are various challenges for designing polymer seals and bearings for the food industry, such as FDA regulations if the seal or bearing will be in contact with food products or the ability to withstand intensive cleaning and sterilization.
Famous Seal Disasters in History: Space Shuttle Challenger
There are many myths related to the Challenger disaster, but one fact remains: the explosion could be traced back to an o-ring that failed to seal in the gases it was responsible for.