How dangerous are hydraulic excavators? Not very – if they are used properly. But when employees forget basic safety procedures, even for a moment, the consequences can be serious.
The National Institute for Occupational Safety and Health (NIOSH) cites an example straight from the sewer construction and maintenance industry. A 28-year-old laborer and a co-worker, and an excavator operator were using a machine with a quick-disconnect bucket to load concrete manhole sections onto a truck.
The laborer was on the ground to connect the manhole sections to the excavator, while the co-worker was on the truck, disconnecting the sections after they were loaded. The operator had positioned the excavator bucket near a manhole section, while the laborer attached a three-legged bridle to the object for lifting. The bucket disconnected from the excavator stick and struck the laborer, who was pronounced dead at the scene.
NIOSH advises business owners and employees to help prevent injuries and deaths through training, proper equipment installation and maintenance, safe work practices, and personal protective equipment.
Based on a review of information from the Bureau of Labor Statistics Census of Fatal Occupational Injuries, NIOSH suggests that the two most common causes of injuries around excavators are being struck by the moving machine, swinging booms, or other machine components, and being struck by buckets that detach unexpectedly. Other leading causes are rollovers, electrocutions, and slides into trenches after cave-ins.
NIOSH suggests a series of measures employers should take to protect workers:
Site setup. Contact local utilities or one-call services to locate overhead and underground utility lines before starting work. Avoid working near overhead power lines. If people must work near them, develop a plan to avoid contact and to follow OSHA regulations for minimum clearance. Do not allow excavators to be operated on grades steeper than those specified by the manufacturer. Make sure workers position machines at a safe distance from trenches or other excavations.
Equipment operators. Train operators in the proper use of the equipment.
Continually evaluate safety programs to address changing work site conditions. Clearly identify and label all machine controls and make sure that the manufacturers’ safety features are working.
Install and maintain equipment attachments and their operating systems according to manufacturers’ specifications. Securely latch attachments (such as quick-disconnect buckets) before work begins. Follow the manufacturers’ instructions for using positive locks on quick-disconnect equipment.
Train operators to conduct visual and operational checks on all machine systems and operating controls before working the machine. Make frequent visual inspections of quick-disconnect systems, especially after changing attachments.
Use the ROPS and seat belts supplied by the manufacturer. Do not remove the ROPS. Do not exceed load capacities when lifting materials. Instruct operators to lower the boom to a safe position with the bucket on the ground and turn off the machine before stepping off for any reason.
Other site workers. Train workers to recognize and avoid unsafe conditions and to follow required safe work practices.
Make all workers aware of the machines’ swing areas and the operators’ blind spots before the operator works the machine. Keep workers on foot outside these areas by marking them with rope, tape, or other barriers.
Before each work shift begins, review and confirm communications signals between machine operators and workers on foot. Instruct machine operators to keep the bucket as close to the ground as possible when workers are attaching loads for hoisting.
Keep workers outside the swing areas and clear of attachments when using the machines for hoisting materials. Do not allow workers to stand under suspended loads or suspended machine components such as the boom, arm, or bucket. Do not permit workers on foot to approach the excavator until they signal the operator to shut down the machine and receive acknowledgment.
Use spotters or signal persons around operating equipment when necessary.
Never permit workers to ride in or work from excavator buckets. Provide appropriate personal protective equipment and make sure that workers use and maintain it.
