Keeping pallets dry through a wet Memphis year

BOX 01The number that matters

Wood with a moisture content below 20 percent will not support mold, mildew, decay or fungus, per Pallet Enterprise. Above it, growth is possible. Memphis normally gets 53.68 inches of precipitation a year, according to the National Weather Service, and humid summers keep outdoor wood damp even without rain.

BOX 02What to do on a dock

• Keep pallets off the ground, on a rack or on skids.
• Keep them under a roof or a cover that does not trap moisture.
• Leave gaps between stacks, since even slight air velocity of a few feet per second can help prevent mold.
• Rotate stock so the oldest ships first.
• Do not load treated pallets into a trailer while still hot.

Heat treatment does not make wood immune to mold. Heat-treated pallets loaded into vans while still hot are susceptible. The treatment kills pests; it does not make the wood stay dry afterward.

BOX 03Who needs to care most

Food and medical docks cannot take a damp or moldy pallet: a clean Grade A, dry from storage to dock, is the standard they ask for. See food and beverage and medical supply and devices. Exporters need dry treated wood as well, since a moldy pallet can be refused at a border; see heat-treated pallets.

A wet pile is a harder sell, too: say in the request if yours has been rained on.

BOX 04A weekly habit for a damp dock

• Check the bottom layer of each stack, where damp collects.
• Look for white or green fuzz on stringers and under deck boards.
• Pull any pallet that smells musty.
• Turn stacks so air passes between them.

These are habits, not a program. They cost minutes and keep a pile out of the cores bin.

BOX 05Rain, shade and airflow

Three conditions favor mold: moisture, warmth and still air. Memphis summers supply the first two. Stacks that sit in shade with air passing between them dry between rains; stacks in a closed corner stay damp. Moving a stack six feet into the sun can make the difference between clean and moldy wood in a month.