Flax seed is safe to store at 11 percent moisture. Higher moisture will result in heating and mold formation. Flax seed often comes from the combine with large amounts of green weed seed dockage. It is a good management practice to remove green dockage before storage. Flax is more difficult to manage in storage than cereal grains.
Systematic monitoring is recommended.
Flax seed has a low angle of repose. Care must also be taken to have tight storage bins. Even small holes and cracks will result in bin leakage. Enter flax bins with caution. Flax seed in storage flows easily and supports limited weight.