A loader operator is assigned to fine-grade a sub-base for a new asphalt pavement. The specification requires a tolerance of +/- 25 mm over 10 metres. Which of the following attachments and techniques would provide the most accurate results?

Question: A loader operator is assigned to fine-grade a sub-base for a new asphalt pavement. The specification requires a tolerance of +/- 25 mm over 10 metres. Which of the following attachments and techniques would provide the most accurate results?

Answer options: ✅ A fixed-blade grader attachment with a laser guidance system, making multiple passes.

• A general-purpose bucket, relying on visual estimation and a spotter.
• A dozer blade on float mode, making single, fast passes.
• A ripper attachment to loosen the material, then a standard bucket to level.

Correct answer: A fixed-blade grader attachment with a laser guidance system, making multiple passes.

Explanation: A fixed-blade grader attachment, especially when coupled with a laser guidance system, offers the precision required for fine grading to tight tolerances like +/- 25 mm. Visual estimation with a general-purpose bucket is insufficient for such accuracy, and a dozer blade on float mode may not offer the consistent control needed.