Frank had worked as a foreman for Warner Roofing Co. for several years. He took safety seriously and worked hard to ensure no one on his crew suffered a serious injury.
One summer afternoon, Frank and his crew were installing asphalt shingles on a residential, steep-slope roof. He and the crew had discussed potential safety hazards, including falls and cuts, and ways to avoid them. The workers had installed appropriate fall-protection systems. They installed slide guards as work platforms, and workers wore personal fall-arrest systems because the roof slope was 9-in-12 (37 degrees). Additionally, Frank made sure his workers wore proper personal protective equipment. Ladders were set on firm ground at the proper ratio: 1 foot away from the building for every 4 feet in eave height, extended 3 feet beyond the eave and securely tied off.
The job required four roofing workers. Two workers were operating compressed air nail guns to fasten the shingles. The workers had been trained to operate the nail guns safely. Frank also made sure the crew did not damage or put kinks in the hoses, which could cause the nail guns to malfunction. He insisted the workers hang the hoses over the house's ridge and toward the work area to minimize tripping hazards and keep the hoses from tangling with workers' lifelines.
When work was completed for the day, Frank and the crew tied in the roof and began to pack up the tools and equipment. As the workers were putting their nail guns away, one young worker, Ryan, suddenly cried out in pain. Although he knew how to operate the nail gun, he incorrectly had disconnected the air hose from the nail gun, loosening the quick-release connection and not realizing air remained in the hose. The force of the remaining air snapped the connection-end of the hose out of his hands, and the hose struck his head just above his right eye.
Frank, a trained first-aid provider, raced to the company truck and grabbed the first-aid kit. He found disinfectant and thoroughly cleaned the cut on Ryan's head. Then, he covered the wound with sterile gauze and bandages. Although Ryan seemed OK, Frank decided to drive him to the hospital and have a doctor check his head wound. Before leaving for the hospital, Frank used his cell phone to call Warner Roofing's owner, Jerry.
At the hospital, a doctor examined Ryan. Ryan's head injury required a few stitches, but otherwise he was fine. Jerry arrived, and Frank explained how the accident had occurred.
Jerry spoke with Frank about additional safety training for Warner Roofing's workers. Although the crew had been trained in safe work practices and taken precautions at the job site, Ryan still had been injured. For Jerry, one injured worker was one too many. What if Ryan's head injury had been more serious?
The following day, Jerry gathered the workers together and guided them through the necessary steps to safely assemble and disassemble tools and equipment that operate using compressed air. He emphasized that only workers who are trained properly should operate such tools.
When disconnecting the hose from the nail gun, Ryan should have held both the tool and connector. Instead, he had let go of the hose, forgetting it had a quick-release connection device. The force of the remaining air in the hose was enough to snap the connection and cause the injury. Before a pneumatic tool is disconnected, the air supply must be turned off at the control valve. Hose ends must be secured to prevent them from whipping if the hose accidentally is cut or broken.
Air supply shut-off valves should be located as close as possible to the point of operation. Any valves, gauges and other regulating devices installed on compressor equipment must be installed in such a way that they cannot be made inoperative.
The air intake must be able to draw air from a clean outside source. Screens or filters can be used to clean the air. Air compressors should not be operated at speeds faster than a manufacturer's recommendation. Compressors should not be allowed to overheat. Also, any moving parts, such as pulleys, flywheels and belts, must be guarded.
There were plenty of roofing jobs coming up, and Jerry knew his workers would need to continue to use nail guns to install asphalt shingles. Jerry decided a regularly scheduled safety review was necessary to avoid another accident involving tools, equipment and compressed air.
Peter Greenbaum is NRCA's director of education and training media.