Roof-mounted hoists are a convenient and inexpensive means of lifting materials to floors above ground level as well as the roof itself. They can be easily installed and dismantled by construction crews, and their simplicity makes them usable by your crews with a minimal amount of training. However, if you are using roof-mounted hoists, or you have plans to use them on your job site, it is important to keep safety considerations foremost. Even these relatively small pieces of equipment can cause serious injury to your workers if safe working procedures are disregarded. Below are several principles of safe hoist installation and operation to implement and enforce on your job site:
Inspect components frequently
Roof-mounted hoists consist of several components, such as a frame, motor unit, control unit, cable and lifting accessories. Failure in any one of these can lead to dangerous accidents, and inspection of these components before, during and after operation is necessary. To provide structure to inspections, implement the use of a manufacturer-provided inspection checklist that must be completed by operators at the beginning of each shift. In addition, don't forget to inspect components that are in a state of disassembly; attempting to assemble a damaged or defective frame, for example, can lead to a collapse when a load is placed upon the hoist.
Be alert for possible electrocution hazards
All lifting devices, including the simplest hoist, are vulnerable to exposure to electrical hazards. The use of metal components and wire cables can make electrical contact deadly to operators and those in the vicinity. That is why hoist placement must take into consideration nearby power lines; install hoists so there is no opportunity for framework or cables to touch them, even in unplanned events such as high winds or equipment failure such as boom collapse.
Replace damaged wire rope immediately
Wire rope failure can occur unexpectedly, even with ropes that seem to have little signs of damage other than kinking or a few broken strands. That's why you must be diligent about using wire rope that is in pristine condition. Any signs of damage to wire rope, including flattening, spreading and rusting, means replacement is required before use should be permitted to continue.
In addition, be sure to fully unwind and take a closer look at the full length of wire rope, not just the visible working section. Damage even to these areas mandates an immediate replacement of the full length of rope. Finally, keep in mind that the proper care of wire rope is a must to protect your equipment and personnel.
Use an appropriate ballast for the hoist
The ballast for your roof-mounted hoist is a vital component of the system, and its absence or deficiency could cause the hoist to topple, taking both men and material with it. There are a number of appropriate ballast materials, so be sure to follow manufacturer specifications when making a decision regarding what type of ballast you will use. Besides those, be sure to use ballasts that are incapable of rolling or sliding away from the hoist frame. In addition, never use building materials that are in use at the job site; for example, on a site where roofing is underway, do not ballast the hoist with shingles or roofing aggregate materials. An unaware worker may inadvertently draw these materials from the ballast stack.
Prepare for competent, safe operation
Despite their simplicity and ease of use, it is necessary for operators to undergo the appropriate level of training needed to use roof-mounted hoists. Training can be as simple as on-the-job instruction from an experienced operator, or it could involve video or computer simulation, depending on the equipment in use. Along with training, a set of comprehensive manufacturer operating instructions should be available at all times. These instructions should be kept in an accessible location, not tucked away in a filing cabinet off-site, and they should also include tables that provide information regarding lifting capacity and other relevant specifications.
For more information on roof-mounted hoists or safety with crane equipment, talk with equipment suppliers, such as Winslow Crane Service Co.