A surprising amount of product loss in industrial chemical storage isn't chemical degradation at all — it's moisture absorption turning free-flowing powder or flakes into a solid, unusable block. A few storage habits prevent most of it.
Why It Happens
Hygroscopic chemicals — caustic soda flakes, calcium chloride, many of the salt and mineral powders we stock — actively pull moisture from the surrounding air. Once enough moisture is absorbed, the material partially dissolves at the surface and then re-solidifies as the local humidity drops, caking into a hard mass that's difficult to dose or handle.
Storage Practices That Prevent It
- Keep original packaging sealed until use — don't open a full bag or drum just to check contents, then leave it loosely closed.
- Store in a dry, temperature-stable area away from direct sunlight; temperature swings that cause condensation inside packaging are often the real culprit, not ambient humidity alone.
- Reseal partially used containers tightly and use them before opening a fresh one — stock rotation matters more for hygroscopic material than for most other chemicals.
- Elevate pallets off concrete floors, which can wick ground moisture into stored bags over time.
If Caking Has Already Happened
Mild caking can sometimes be broken up mechanically without affecting the chemical itself, but heavily caked or partially dissolved material should be tested before dosing — the effective concentration may no longer match the label. When in doubt, treat caked stock as suspect rather than assuming it's still at full strength.