What steps should be taken if air content test results are outside specification?

• A. Stop placing, document the result, investigate potential causes (moisture content, mix design, aggregate moisture), and take corrective action or report.
• B. Continue placing until the next batch.
• C. Temporarily adjust slump to fit target.
• D. Ignore and proceed.

Answer: (A)

When air content tests are outside the specification, the immediate priority is to prevent placing more concrete until the issue is understood and corrected. Stop placing, document the result, and begin a quick root-check of what caused the deviation. Look at the aggregate moisture content and how it’s being accounted for, because moisture can steal or add air in the mix. Check the mix design and the dosage of the air-entraining agent to see if they’re correct for the current materials and conditions. Confirm that the testing was done correctly and that the air meter is calibrated.

Using what you find, take appropriate corrective actions such as adjusting the air-entraining agent dosage, correcting moisture calculations, or revising the batch so the target air content can be achieved. After making adjustments, perform a retest with a fresh batch or the corrected batch. Only resume placement once the air content is within specification and all steps are properly documented and reported as required.