A crane's load chart specifies different capacities for 'On Outriggers Fully Extended' versus 'On Tires - Stationary'. If a lift is performed with outriggers only partially extended, what must the crane operator do according to CSA Z150?

Question: A crane's load chart specifies different capacities for 'On Outriggers Fully Extended' versus 'On Tires - Stationary'. If a lift is performed with outriggers only partially extended, what must the crane operator do according to CSA Z150?

Answer options: ✅ Refer to the 'On Tires - Stationary' chart or the manufacturer's specific 'partially extended' chart if available.

• Use the 'On Outriggers Fully Extended' chart and apply a 25% reduction factor.
• Interpolate capacities between 'Fully Extended' and 'On Tires Stationary' charts.
• Perform a test lift with a load equivalent to 110% of the planned load.

Correct answer: Refer to the 'On Tires - Stationary' chart or the manufacturer's specific 'partially extended' chart if available.

Explanation: CSA Z150 mandates that when outriggers are not fully extended, the crane's capacity must be determined from either a specific chart provided by the manufacturer for that configuration or, in the absence of such, the 'On Tires - Stationary' (or the next most restrictive) chart must be used to ensure safety. No interpolation or arbitrary reduction factors are permitted unless specified by the manufacturer.