Meaning
Correction applied to the gross weight of a bulk material shipment to account for water content detected during sampling. Industrial facilities use a moisture deduction to ensure they only pay for the dry weight of the metal or ore they are purchasing. Since water adds significant mass but no industrial value, accurate measurement of humidity is a standard part of the receiving process.
This adjustment prevents sellers from profiting by delivering wet material that would otherwise skew the settlement weight.
Quality Adjustment
Samples are taken from different parts of a load and weighed before and after being dried in a specialized oven. The percentage of weight lost during this heating process determines the moisture deduction for the entire shipment. If a ten ton load of scrap contains five percent water, the buyer will only pay for nine and a half tons of metal.
This protocol is applied to materials stored outdoors or those that naturally absorb water, like certain mineral concentrates.
Commercial Valuation
Contracts between buyers and sellers include specific clauses that define how the water content will be measured and at what point a penalty might apply. A moisture deduction is not just a weight adjustment but also a way to account for the energy needed to evaporate the water in the furnace. High levels of liquid can also be a safety hazard, causing explosive steam releases when added to a molten metal pool.
Keeping the material dry is in the interest of both the logistics provider and the end user.
Testing Method
Automated sensors and manual oven tests provide the data needed to calculate the final invoice. The moisture deduction must be documented on the receiving report and shared with the supplier to maintain transparency. If the results are outside the normal range, the load may be held for a second test or rejected entirely.
This rigorous approach to weighing is a fundamental part of inventory management in the bulk commodities sector.
