Before beginning the slump test, the slump mold should be in what condition?

The slump mold should be dry before beginning the slump test to ensure accurate and reliable results. A dry mold allows the concrete to adhere properly during the test and helps to prevent any interference with the measurement of the slump. When the mold is dry, it minimizes any potential effects of moisture on the concrete's consistency and prevents it from sticking to the mold, which could lead to an incorrect slump reading.

When the mold is wet or moistened, it can absorb water from the concrete mix or introduce extraneous moisture, potentially affecting the slump measurement. Coating the mold with oil is also not appropriate, as it could create a barrier that alters the interaction between the concrete and the mold, leading to inaccurate results. Ensuring that the mold is dry aligns with standard practices that dictate conditions necessary for conducting the slump test effectively.