Methods include:

Filtration Systems: Installing high-efficiency filters to remove particles.
Breathers and Seals: Using desiccant breathers and maintaining seal integrity to prevent moisture and particle ingress.
Oil Purifiers: Utilizing centrifuges or vacuum dehydrators to remove water and gases.
Regular Monitoring: Conducting oil analysis to detect contamination early.
Good Housekeeping: Maintaining cleanliness during oil handling and storage.
Implementing these methods minimizes the risk of contamination, enhancing oil and equipment longevity.