When Should Tower Cranes Stop Operating in High Winds?
The decision to suspend tower crane operations due to wind is not based on a single universal figure, it depends on the manufacturer’s specifications, crane configuration and type of lifting operation. However, there are established industry thresholds and standards used across UK construction sites.
General Industry Guidance
Most tower cranes in the UK are designed and operated in accordance with:
➜ BS EN 14439:2006+A2:2009 – Cranes: Tower cranes – Safety.
➜ BS 7121-5:2019 – Code of practice for safe use of cranes – Tower cranes.
Under these standards:
➜ Lifting operations are typically suspended when wind speeds exceed 38–45 mph (17–20 m/s).
➜ No slewing or trolleying should occur above this threshold.
➜ Operators must constantly monitor real-time wind speed using anemometers (fitted on the jib or cab).
➜ For mobile cranes, the limit is usually lower — often around 31 mph (14 m/s) — but again depends on load radius and configuration.
Out-of-Service Conditions
When wind speeds are expected to exceed the operational limit:
➜ The crane must be placed out of service following the manufacturer’s procedure.
➜ This includes free-slewing (allowing the jib to weathervane) and securing the hook block, cabin and load line.
➜ The operator should verify that free slew is functional before leaving the cab.
Failure to do so can result in structural overload, mast buckling, or crane collapse during high winds, as has tragically occurred in past UK incidents.
Monitoring and Controls
Best practice on major London sites includes:
➜ Continuous wind monitoring at jib height, not ground level.
➜ Automatic alerts to the site team when gusts approach 90% of the operational limit.
➜ Logging of wind data for each lift in the lifting plan and daily record.
➜ Liaising with the Appointed Person or Crane Coordinator before resuming operations after strong gusts.
Practical Rule of Thumb
➜ Below 30 mph (13 m/s): Lifting generally safe (subject to load and configuration).
➜ 30–38 mph (13–17 m/s): Caution — review loads, reduce radius and plan pauses.
➜ Above 38–45 mph (17–20 m/s): Stop operations; place crane out of service.
➜ Above 55 mph (25 m/s): Check integrity of tie-ins, mast bolts and weather-vane clearance even when not in use.
Most UK tower cranes should cease lifting operations once wind speeds reach around 38–40 mph, and be safely weather-vaned before gusts exceed 45 mph.
