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Chipping Away at Chipper Safety
Tree Care Industry, the monthly magazine of the Tree Care Industry Association, September 2008 issue
By Rick Howland
The tree care industry can be a dangerous one, but is becoming less so as the days go on, thanks to two things that can work independently or in concert with one another: Safer equipment and better operator training.
The chipper is a perfect example. You might think you recognize all the improvements that have been made in chipper technology over the years, but you are likely to be wrong. Sure, you can click off the major steps in safety and training, but there is some very subtle, very effective engineering that's working on your behalf, thanks in large part to a savvy manufacturing group that wants you and your employees to be efficient in your job and safe enough to, yes - go home to your family each night, but also to come back and buy more, bigger and better machines.
Case in point is Vermeer. According to Todd Roorda, solutions specialist for the environmental business segment at Vermeer Corporation, "In 1985, Vermeer established the first successful configuration of the feed intake for brush chippers that provided a strategic shape and size to help keep operators away from the feed rollers and knives of mechanically fed brush chippers."
 This safety strategy is often referred to as "safety distance guarding." Since most brush chippers are hand-fed, it clearly makes sense to put distance between the operator and the feed rollers. The structure that defines this shape serves as a mechanical barrier so the operator cannot touch the feed rollers while standing on the ground. It also helps prevent an operator from being pulled into the feed rollers by a limb. This strategy has been highly successful and has been adopted in various ways by most manufacturers today.
Another feature developed by Vermeer is a bottom feed stop bar strategically located at the end of the feed table, where it is possible for the operator's leg to strike the bar and stop the feed either intentionally or automatically in an emergency situation.
 "The feed stop bar is set up so the operator does not have to reach for a safety cable or bar," says Roorda. "The operator's leg will bump the feed bar and disable the feed roller automatically."
This patented feature includes dual sensitivity settings so the operator can reduce the sensitivity of the bar in difficult feeding conditions. This selectable sensitivity feature together with the location and design of the bar are intended to minimize the potential for limbs striking and tripping the bar while also providing an important safety advantage. Along with the bottom feed stop bar, an upper feed control bar now adds another stop position to allow the operator to stop the feed by either pushing or pulling the bar.
"These features are built into every Vermeer chipper," Roorda says.
"We also have a program called Tech Reach in collaboration with Manpower nationally and with other manufacturers for people wanting to learn to be climbers or run chippers," says Roorda. "We do multi-day events that go through various disciplines, including operator safety, from how to hook up and tow your chipper to its safe operation."
The most recent addition to the Vermeer chipper line is the BC2100XL, a 21-inch chipper launched in January 2008. This unit is designed to accept entire trees, so it's popular with contractors doing site prep and land clearing as well as some residential takedowns.
"With the 2100, you don't have to spend a lot of time de-limbing a tree. This machine has more pulling power (10,000 pounds) and crushing power (4,500 pounds) than any other chipper we've designed. This increases efficiency enormously," Roorda concludes.
"What we talk about most is physical safety," says Dennis Beam, former president of Woodchuck Chipper Corp. and now sales manager for Altec Environmental Products. "It is part of the company's whole philosophy about being smarter and safer."
The same is true for Altec's Sentry training program, according to Beam, which offers either computer-based or on-site instruction for every Altec product, leading to user certification on proper equipment usage and injury reduction. (Altec has trademarked its brand statement, "Helping crews work safer and smarter.")
"The panic bar was introduced a couple of years ago at Woodchuck and carried over to Altec products," Beam says. "We think this is the premier safety device for chippers in the industry, and Altec continues to refine and to make the bar more user friendly into its second or third generation." This is the bright green bar set up between the operator and feed system and is standard on all Altec Environmental Products equipment featuring the control feed system. (With self-feed types, Beam says there is no way to incorporate that bar.)
He adds that Altec continues to ensure that all safety guarding is correct on all products to meet all standards, and takes steps to ensure that operators are protected from moving parts while operating the machine or accessing the machine for maintenance.
"We have secured the machine to include padlocks, which slows operator access to ensure that the machine has stopped r otating and also to ensure that only authorized and properly trained personnel have the tools and can access those areas," he says.
The actual configuration of some Altec models is also contributing to safety. Beam notes a growing interest in what is called the curb-feed system, which allows an operator to side-feed and thus avoid feeding from the back of the chipper, an important consideration when the operator's back is facing oncoming traffic in urban areas. The curb feed offered in 12-inch models is set up to allow operators to face rearward, toward oncoming traffic, and removes them from being between the traffic and the machine.
Additionally, on models featuring a winch (standard on larger models), Altec employs not a steel cable, but, rather one made of a material that does not store energy under strain (think a stretched rubber band) with the potential of lashing about if snapped, thus potentially injuring an operator or damaging the chipper. Instead, Beam says, if the line breaks under load, it merely drops to the ground.
 "Finally, he says, "There is no substitute for training, and there are warning labels on each machine."
Rob Faber, commercial sales specialist at Morbark, says safety is the most important issue at the company. "Our major safety measures include the length of the infeed chute, some 85 inches from the pinch point of the feed wheel to your feet. This is a general rule intended to ensure that the operator is kept at a safe distance from the business end of the chipper," he notes.
Next, Faber says, there are two safety cables in the infeed chute. "If an operator feels he is being pulled in or getting caught up, there are two hanging cables to pull on that will cause the feed bar to go into reverse."
"We also feature a safety switch on the chipper hood. If you pull the pin that holds the hood in place while the engine is running, it will shut down the machine and will not allow it to restart until the pin is replaced."
Morbark makes eight chipper models with capacities ranging from 6 to 20 inches, and with horsepower ratings from 25 to 325, Faber says.
Jerry Morey, president of Bandit industries, says chipper safety is an industry-wide issue. "We would like to thank all the tree care services that have instituted regular chipper safety training programs, and we also applaud the efforts of the industry trade associations that are working hard to make worker safety a top priority."
 "At Bandit, we continue to stress proper safety training and operation as the best way to avoid accidents. Above all, always follow ANSI and OSHA standards," says Morey.
"We do our part as well," Morey says, pointing out the safety features on all Bandit chippers. These include guards to cover the hydraulic pump belt drive, chipper drive belts, feed wheel drive couplers and bearing retainer; awooden pusher paddle to help the operator feed small wood debris; safety decals prominently displayed and available in multiple languages (Spanish/English combination now standard); patented mechanical spring lock pin that prevents the disc's hood pin from being removed when the disc is turning. (The disc's hood won't open until the disc has come to a complete stop) and a padlock to prevent unauthorized persons from accessing the disc or drum; patented last-chance pull cable located inside the infeed hopper and used to stop and reverse the feed system; patented fold-down infeed tray cushioning springs, which reduce the effort required to raise and lower the in-feed pan (standard on larger, heavier Bandit chippers, from Model 250XP on up); availability of equipment in two safety colors, Bandit yellow or alert orange; and an electronic limit switch on the disc/drum hood-pin lock-out to prevent the engine from being started without the hood pin in place.
Safety also involves ergonomic design, Morey says, so "look for low-risk positions for any operator, such as low force, low stress operation, no repetitive motion functions required for operation, and easy-to-read gauges."
Chuck Ritz, president of Karl Kuemmerling, maker of the Mitts & Merrill brand chipper, is convinced that the basic technology of a chipper contributes to its safety, and that is why he advises buyers to purchase a drum-style chipper, which he says is unlikely to pull an operator through the cutting area.
 "When feed-roll chippers first came out, they were said to be the safest on the market, but it didn't prove out to be that way," opines Kuemmerling. "To my way of thinking, the drum style is safest, although the feed-roll types have their advantages in being able to take in vines and branches."
Safety is a process that needs to be shared with the industry, according to Sal Rizzo, president at Salsco, which he says has been making its chippers with safety bars and emergency stop buttons in the feed-operator area for nearly 20 years.
"Our equipment has been safe right along, and we would not put one on the market that wasn't," says Rizzo. "It doesn't matter who is first with new technology, it matters that all equipment has it. If we come up with a safety device, I feel strongly that everyone should have access to it. That's why we do not patent ours."
Salsco makes chippers ranging from 3.5 inches to 18 inches, both PTO and engine driven, and manufactures other products for six different industries, Rizzo says, "so safety is a big concern."
New to the chipper market is U.S. Praxis, known for its splitters and stump grinders until the spring of this year.
"Building on its success in the log splitter and stump grinder markets, U.S. Praxis recently entered the chipper field with the Praxis Wood Chipper," says Jim Cornelius, company president. "Our goal was to build a wood chipper that was small enough to fit through a standard 36-inch gate but with a large enough chipping capacity to take on 6-inch limbs."
In the past, Cornelius notes, users shied away from gravity-fed chippers due to a tendency for debris to kick back at the person feeding the machine. He calls it "chuck and duck." Praxis overcomes this with a rubberized screen for additional safety.
"Another safety feature is an operator safety switch on the cover of the flywheel," he says, "so that, if the cover is opened, no one can start the engine."
"We take a simplistic outlook," says Bob Engler, president and owner of Woodsman. "We feature a three-sided control bar that protrudes from the structure of the feed hopper, allowing easy access to the control bar. We don't do pull cables and some other features because our view is that we abide by ANSI recommendations, and, second, events happen so quickly that operators don't have much time to think. We think the three-sided control bar is safest and we make it standard on all Woodsman units. That way, it's simple for a quick reaction by an operator or someone standing by."
Woodsman makes drum style chippers in four models, from 6 inches to 20 inches, and also has a full line of biomass chippers used to make fuel for biomass energy generators.
In addition to exceeding the reach standards (edge of the tray to the pinch point of the feed rollers), Echo Bear Cat features a unique four-position control bar (reverse, forward, neutral and reverse again). This gives the operator two opportunities to throw the hydraulic-feed machines into reverse, thus backing material safely out of the feed area.
According to Joe Dietz, product manager for Echo Bear Car products, "What we do is unique in that the hydraulic-feed models, featuring a reverse on both ends of the control bar. If an operator feels a threat as a branch is drawn in, he can do what's easiest - either pull or push the feed roller control bar and get the feed into reverse to back material out."
Conclusion
Safety is everyone's concern, says Tim Walsh, who has taken a particular interest in chipper safety and has spoken on the subject at TCI EXPO (see sidebar, page 36). As you look at the offerings in today's market, Walsh says, consider that the manufacturers are doing what they can technology-wise, but also doing what they can to help you remember that you, the buyer, and your users need to be trained and aware so your chipper remains the asset it was designed to be.
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