The simplicity of vacuum excavation often leads to improper use with new operators.
It seems simple enough – water or air under pressure to loosen soil and a vacuum to suck it up. But as a warning on a new safety video states, “Misuse of this equipment can lead to property damage, serious injury or even death.”
The 19-minute DVD from the Association of Equipment Manufacturers (AEM) is supported by AEM’s 36-page safety manual along with equipment and job site checklists available from its website at www.aem.org. “The vacuum excavation industry is growing rapidly with over 25 manufacturers,” says William Bernhard, manager of Technical & Safety Services for AEM. “The video was produced to promote the safe use of the equipment to help prevent injuries and damage to underground utilities.”
Since vacuum equipment is often rented, the video stresses the importance of reading and following all operating and safety manuals provided with the equipment. “As with most large equipment, the main safety errors are a lack of knowledge of the machine, how it operates and the application being utilized,” Bernhard says. “Plus, a large factor is always speed and hurrying to get the job done.”
The video covers seven major topics, including the importance of calling 811 or another locating service before doing any work:
- Operator safety
- Equipment inspection
- Transporting equipment
- Before starting on the job site
- Operation and maintenance
- Finishing the job
As the video demonstrates using a watermelon, both the vacuum equipment and high pressure water present unique risks for serious injury. Along with normal personal protective equipment, the video suggests full face shields when necessary, snug-fitting clothes that protect from rocks and other objects that can be thrown by the high-pressure stream of water, cut-resistant gloves, shin guards, and electrically insulated boots and gloves when working around energized lines.
Since it is relatively new to the U.S., some people don’t appreciate using the proper pressures and volumes for air and water and figure that more is better. Under normal application, the recommended water volume is under 10 gpm. While the maximum recommended water pressure for straight-tip nozzles is 2,500 psi and 3,000 psi for a rotary nozzle, the video suggests operators use just enough pressure to excavate the soil. Too much water or pressure can erode or undermine the soil and cause damage to nearby structures, such as power poles and streets. The video also warns against using sewer vacuum equipment for vacuum excavation because it is not designed for such use.
While vacuum excavation may look easy, Bernhard says that only multiplies the risk of injury. “Training is always necessary when operating equipment. As vacuum excavation becomes more popular with experienced and knowledgeable operators, these machines are being used appropriately. Without proper training, people often overlook the precautions that experienced operators use.”
Five members of AEM’s Underground Equipment Manufacturers Council – Ditch Witch, Sewer Equipment, Vacall, Vactor and Vermeer – collaborated with AEM on the writing and planning of the video, which was produced by a professional production company. The DVD is available for purchase at AEM’s online store for $19.95 ($49.95 for nonmembers). AEM’s vacuum excavation safety manual is available for $2.25 ($2.75 for nonmembers).