Drive a lift truck or operate an overhead crane, and there are pages and pages of OSHA safety standards to protect you. The same is true if you're securing trucks or trailers to a loading dock or unloading crates of orange juice in a grocery stockroom. And if "work" means deboning a chicken or sitting in front of a computer terminal, OSHA has rules in place for preventing injuries to your wrists or your eyes. But if you work with or around conveyors, you're on your own.
Conveyors are at the same time one of the most useful and one of the most dangerous pieces of equipment in the DC. Between 9,000 and 10,000 accidents—and 30 to 40 deaths—are attributed to conveyors each year. Even so, OSHA has never enacted its own conveyor safety standards. Instead, the agency relegates conveyor safety to its general duty clause section, a kind of generic section of the Occupational Health and Safety Act that addresses areas not covered by any specific standard.
George Schultz thinks that's unacceptable. "If OSHA had done something in 1970 when it initially considered the issue, it could have reduced conveyor accidents by 50 percent," says Schultz, who is vice president of Siebert Engineers in Lombard, Ill., and the author of a book titled, appropriately enough, Conveyor Safety. Indeed, Schultz has spent the last three decades trying to change attitudes and persuade the industry to adopt professional standards.
Without OSHA's leadership, Schultz charges, what's left is an industry with very little incentive to focus on worker safety. "Presently, there is only one book written on conveyor safety, two videotapes and a limited number of training classes available on the subject," he says. "Never in my 55 years in the industry have I been hired by anyone to look at the safety of their conveyors."
That leadership void has left manufacturers struggling to regulate their own activities. The major manufacturers meet regularly in such bodies as the Conveyor Equipment Manufacturers Association (CEMA) to stay on top of safety trends. "As a member of CEMA, we get an industrywide picture of safety issues associated with conveyors," says Chuck Waddle, executive vice president for FKI Logistex's automation division.
Steering clear of belts that buckle is not enough. To ensure safe conveyor operation, the FFVA Mutual Insurance Co., based in Orlando, Fla., has come up with these 12 basic rules for safe conveyor operation:
1. Don't perform service on a conveyor until the motor disconnect is locked out.
2. Service conveyors only with authorized maintenance personnel.
3. Keep clothing, fingers, hair and other parts of the body away from the conveyor.
4. Don't climb, step, sit or ride on a conveyor at any time.
5. Don't load the conveyor outside of the design limits.
6. Don't remove or alter conveyor guards or safety devices.
7. Know the location and function of all stop/start controls.
8. Keep all stopping/starting control devices free from obstructions.
9. Make sure all personnel are clear of the conveyor before starting.
10. Operate conveyors with trained personnel only.
11. Keep the area around conveyors clear of obstructions.
12. Report all unsafe practices to a supervisor.
But the fact remains, all the manufacturers have to fall back on right now is the voluntary ANSI B20.1 "specification" standard, which represents the most comprehensive safety standard available today. Under the standard, the responsibility for safety is divided among the owner, management or engineering consultant, the manufacturer (which must build its equipment to the ANSI specification), the installer and the operator or user of the equipment. As a practical matter, everyone—and no one— is responsible.
Safe at any speed?
In the absence of official standards, manufacturers are doing what they can to ensure safe design. Tom Carbott, senior director of sales at the Material Handling Industry of America, a trade group based in Charlotte, N.C., reports that conveyor manufacturers are trying to "progressively make enhancements that will reduce the risk of accidents posed by conveyors."
Waddle says that so far, it's working. "While there haven't been any recent big leaps in design when it comes to safety, there's been a gradual increase in safety features over the past 10 years," he says. "We have fewer claims and injuries than we did even five years ago."
Certainly, as conveyors become more automated, there's less need for humans to come in contact with the equipment. "Increased conveyor automation can many times eliminate the need for operators to interface directly with conveyor equipment," says Boyce Bonham, manager of the technology center at Hytrol Conveyor Co., based in Jonesboro, Ark.
Another advance in safety has been the introduction of 24-volt-powered conveyors, adds Ken Bobick, global product manager at Interroll of Wilmington, N.C. "The 24-volt product has low power, with a low current, and can be stopped with a hand," he says. The 24-volt models typically compete with mechanically driven equipment (i.e., beltdriven or line-shaft conveyors). The 24-volt equipment works by controlling individual sections of a conveyor. Power consumption is reduced because it's only used when needed.
Another design enhancement that makes the equipment safer is the zero pressure feature. "The advantage to zeropressure conveyors is that they don't run continuously, so there's no motion if none is required," explains Bobick. Reduced motion, he says, means reduced chances for accidents. Zero pressure systems use photo eyes mounted in various places to sense the presence or absence of packages. This allows the systems to keep packages spaced out to avoid collisions.
Hytrol's zero pressure system also includes jam protection, which prevents back pressure in jammed conditions. "This often allows the equipment to clear jams without operator assistance," says Bonham, "and that certainly lessens the difficulty of clearing a jam if operator assistance is needed, making the operation safer."
Manufacturers also offer guards, covers and panels aimed at keeping end users from making contact with moving parts like chains, gears or "nip points." (A "nip point" is the point at which an element of the conveyor machinery moving in a line or rotating meets another element that is moving in a line in a manner that makes it possible to nip, pinch or entrap an object coming in contact with one of the two elements.) They'll also provide warning labels that graphically illustrate hazards associated with conveyors. Most manufacturers encourage their customers to display these labels in a prominent place.
Getting smart about safety
Yet warning labels cannot compensate for unsafe behavior. End users must do their part to keep employees safe. Too often, that doesn't happen. "Very few customers inquire about the equipment's safety features," says Waddle."Buyers just assume we meet 'OSHA requirements' and don't ask anything else."
In some cases, buyers even reject the most basic of safety features, says Waddle. "Many customers don't want emergency stops that turn off the entire system," he says. Without that feature, they cannot react to an emergency simply by hitting a button that shuts down the system. Instead, they have to figure out which emergency stop they need in the heat of the moment.
Schultz adds that very few users install warning lights or buzzers to let employees know when a conveyor is going to start up. "Probably 90 percent of conveyors don't have warnings to alert users about startup," he says.
What Schultz and others would like to drive home to end users is that investing in the many types of guarding systems is essential, as is ensuring they are installed and used properly. Users must also make sure the equipment meets the job requirements. "Only use a conveyor in an application that fits within its specific design parameter," says Bonham.
The bottom line is that while conveyor manufacturers must do their part to minimize potential hazards associated with conveyor operation, in the end, the onus of conveyor safety falls on the user. Until OSHA issues its own specific conveyor safety standards, Schultz says, "the responsibility will never really be pinned down. And safety information will never be passed around as it should be."