Inclement Weather Planning, Part II
September 3, 2019
Inclement weather conditions can adversely affect hoisting activities for cranes, hoists and forklifts. To ensure the safety of all involved, to protect equipment, and in an effort to keep a job running on schedule, we suggest implementing the following safety measures related specifically to hoisting activities:
Wind speed should be monitored for 24 hours prior to any hoist dates in order to confirm acceptable conditions and to allow ample time to adjust the hoisting schedule as necessary. Wind speed factors to keep in mind are:
- As winds approach 15 mph, consider the weight of the load, the geometric shape of the load, elevation of the lift, ground stability, and wind direction when determining if it is safe to move forward with hoisting activities. If sub-15 mph winds continue to compromise safe hoisting conditions (almost always as a result of load type), postpone activities for that load type until acceptable/safe conditions prevail.
- When wind gusts or sustained wind speeds reach 15 mph to 20 mph, postpone all hoisting activities until wind speed has dropped below 15 mph.
- With respect to forklifts, wind gusts above 15 mph do not generally create a hazard in moving materials on the ground, as long as forklift booms do not extend above 10 feet in elevation.
Cold weather can also affect safety during hoisting activities. Temperatures below 40°F can create conditions that can adversely affect crane hydraulics, derate the crane’s weight-lifting capacity, can result in shock loading events, and can expose crew members to safety and health hazards associated with cold temperatures. Best roofing practices dictate that no work shall take place until temperatures reach at least 40°F.
Additional grounds for postponing hoisting activities include rain, severe fog, snow and lightning. Rain, snow and heavy fog can create slip/fall hazards for employees and can prevent secure rigging of loads. And lightning is an absolute condition for postponement. If satellite imagery illustrates lightning within a 25-mile radius, all hoisting-related activities must cease.
No matter the type of inclement weather, it is the contractor’s responsibility to advise the owner of any postponement of planned hoisting activities. Continuing work in any of the conditions listed above can result in equipment failure, employee injury and/or property damage.
For more tips on how to prepare for and navigate inclement weather events, refer to Inclement Weather Planning, Part I.