The four situations in which the aggregate must be sampled and tested are

1. This situation is the most common and suited for every commercial business. This is referred as preliminary investigation of a supply often the source which could be a rock supply from the quarry, an aggregate deposit from the manufacturer, or an industrial by-product.the supplier has to make a check before investing money in these products before extracting and processing aggregate.
2. When the buyer decides to accept or reject the source of supply. By doing the sampling and testing the buyer determines the quality of the aggregate who is supposed to buy a large quantity of aggregate for one project or a number of projects. For example the public work department which approves or rejects gravel or sand for the state projects.
3. The sampling and testing is done on the time of delivery by the buyer as the final check conforming to the agreement filed. This is followed by the acceptance and rejection of the material at the delivery station.
4. This is done to assure the quality of the aggregate is the same as in the agreement. A test is performed after receiving the material to check to take control over removal and processing.