Pallet moisture content (MC) should be below 15% for export shipments. Wood above 19% MC can release enough moisture inside a sealed shipping container to cause condensation, mould growth, and cargo damage — a problem known as "container rain" that costs exporters thousands of dollars per incident.
If you export goods from Sri Lanka on wooden pallets, the moisture content of the pallet wood is one of the most overlooked risks to your cargo. Here is a practical guide to understanding, measuring, and managing pallet moisture content.
What is Moisture Content?
Moisture content (MC) is the percentage of water present in wood, expressed as a ratio of the weight of water to the weight of the dry wood. It is calculated using the formula:
MC% = ((Wet Weight - Dry Weight) / Dry Weight) x 100
Freshly sawn timber in Sri Lanka typically has a moisture content of 40-80%, depending on the species and season. For export pallets, this must be reduced to below 15% through kiln drying.
Why Does Pallet Moisture Matter for Exporters?
Container Rain
When a sealed shipping container travels from a tropical climate (Sri Lanka) to a colder destination (Europe, Japan, Russia), the temperature inside the container drops. If the pallet wood has high moisture content, the wood releases moisture as the temperature falls. This moisture condenses on the container ceiling and walls, then drips onto your cargo.
This phenomenon — known as "container rain" or "container sweat" — can cause:
Product-Specific Risks
Different export products have different sensitivities to pallet moisture:
For industry-specific guidance, see our pages on [pallets for tea export](/pallets-for-tea-export), [pallets for spice export](/pallets-for-spice-export), and [pallets for coconut export](/pallets-for-coconut-export).
What MC Level is Safe for Export?
The widely accepted maximum moisture content for export pallets is 15%. Some destinations and products require even lower levels:
CeyPall kiln-dries all export pallets to below 15% MC as standard. For moisture-sensitive cargo, we can target lower MC levels on request.
How to Measure Pallet Moisture Content
Pin-Type Moisture Meters
Two metal pins are inserted into the wood surface. The meter measures electrical resistance between the pins — higher moisture means lower resistance. Pin meters are accurate, affordable, and give instant readings.
How to use: Insert pins along the grain, at least 25mm from any edge. Take readings at multiple points on the pallet and average them.
Pinless (Capacitance) Moisture Meters
A flat sensor pad is pressed against the wood surface. The meter measures changes in an electromagnetic field caused by moisture. Pinless meters are faster and do not leave holes in the wood, but can be affected by surface moisture.
Oven-Dry Method
The most accurate method. A wood sample is weighed, dried in an oven at 103°C until the weight stabilises, then reweighed. The moisture content is calculated from the weight difference. This method is used for calibration but is too slow for routine checks.
Use our free [Moisture Content Calculator](/moisture-content-calculator) to calculate MC from weight measurements or convert between meter readings and actual moisture content.
When to Check Moisture Content
How CeyPall Controls Moisture Content
All CeyPall pallets go through our kiln-drying process, which reduces moisture content to below 15%. The heat treatment required for ISPM 15 compliance (56°C core temperature for 30 minutes) is carried out simultaneously with kiln drying, ensuring both phytosanitary compliance and low moisture content in a single process.
We use calibrated moisture meters to verify MC levels before pallets leave our facility. If you have specific MC requirements for your cargo, contact us to discuss your needs.
Published July 3, 2026 · By CeyPall (Pvt) Ltd
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