Regarding the buffer zone around located utilities, how far from the marked centreline of a utility must an excavator avoid mechanical digging and instead use hand exposing techniques, as per common Canadian practice and CSA S250 guidelines?

Question: Regarding the buffer zone around located utilities, how far from the marked centreline of a utility must an excavator avoid mechanical digging and instead use hand exposing techniques, as per common Canadian practice and CSA S250 guidelines?

Answer options: ✅ 0.3 metres (1 foot) on either side

• 0.5 metres (1.6 feet) on either side
• 1.0 metres (3.3 feet) on either side
• 2.0 metres (6.6 feet) on either side

Correct answer: 0.3 metres (1 foot) on either side

Explanation: Common Canadian practice, aligned with principles in CSA S250 (Mapping of Underground Utility Infrastructure) and industry 'best practices', dictates a minimum buffer zone of 0.3 metres (1 foot) on either side of the marked utility line where only hand exposure or non-destructive methods are permitted.