The slump tolerance range must be obtained from which source?

• A. Discharge of mixer
• B. Batch ticket
• C. Field sample
• D. Lab test

Answer: (A)

Slump tolerance range refers to the allowable deviation around the slump value for that concrete batch, and it comes from the concrete as it is produced and leaves the mixer. The actual material you’re accepting is what’s discharged, so the permissible range you use to judge acceptability is tied to the discharge conditions of that batch. In practice, you compare the slump measured on the discharge sample to the tolerance band established for that batch as it comes off the mixer. The batch ticket sets target values, but the range you apply for acceptance comes from the discharge itself. A field sample or lab test is used to measure slump, and the batch ticket alone doesn’t define the acceptable range that applies to the delivered concrete.