A project involves lifting an architectural banner (large sail area) for an event. The site wind speed limit for lifts with exposed surface area is set at 35 km/h, while for standard lifts it's 50 km/h. During the lift, the anemometer reads 30 km/h, but the operator notices sustained gusts visually displacing the banner significantly. What should the operator's primary concern be, and what action is warranted?

Question: A project involves lifting an architectural banner (large sail area) for an event. The site wind speed limit for lifts with exposed surface area is set at 35 km/h, while for standard lifts it's 50 km/h. During the lift, the anemometer reads 30 km/h, but the operator notices sustained gusts visually displacing the banner significantly. What should the operator's primary concern be, and what action is warranted?

Answer options:

• The anemometer reading is below the limit, so continue the lift cautiously. ✅ The visual observation of significant displacement indicates that actual forces may exceed the rated capacity or limit, stopping the lift is warranted.
• The gust factor is not measurable, so operator judgment is the only factor.
• Increase boom angle to reduce effective surface area.

Correct answer: The visual observation of significant displacement indicates that actual forces may exceed the rated capacity or limit, stopping the lift is warranted.

Explanation: Even if the average anemometer reading is below the limit, the operator's visual observation of significant load displacement due to wind indicates that the actual forces are nearing or exceeding safe limits. The operator should immediately cease the lift if safety is compromised, as gusts can exceed the sensor's refresh rate or localized effects can be worse than a single sensor reading.