Reprinted from GRAIN JOURNAL May/June 2020 Issue
This article is based on a webinar by Jerad Heitzler, training manager-Foundations™, Martin Engineering, Neponset, IL (800-544-2947), given Feb. 20 as part of the GEAPS/Grain Journal educational webinar series.
Are you doing enough to prevent injuries from belt conveyors? I’m confident in the belief that many companies are not.
In recent years, belt conveyor safety has attracted more attention from bulk material handling companies, the agencies that govern worker safety, and the workers and their families.
There always have been industry best practices for belt conveyor safety that companies and workers follow, but I still doubt that everyone is doing everything they can do to reduce the likelihood of injury.
Jerad Heitzler
Many companies overrely on signage, personal protective equipment (PPE), and common sense to avoid belt conveyor-related injury. In other words, companies have an expectation that workers have an innate understanding of the hazards presented by belt conveyors and that they can protect themselves. That’s why I believe that we can do more to keep workers safe.
Standard Training Tactics
For most material handling companies, there are four effective, yet flawed, approaches to belt conveyor safety:
• PPE and attire. PPE is the least effective way to prevent injury, because it does absolutely nothing to prevent a worker from getting caught in a pinch point. PPE only potentially reduces the severity of an injury.
• Policies, procedures, and protocol. The problems with things like lockout/tagout programs are that they can be open to interpretation, they are not always enforced, and they are not inclusive of all hazards.
• Training. Training adults is very different and more difficult, than training children. According to a study done by the Association for Talent Development to better understand adult learning, 15% will trust new concepts outright, 50% will trust new concepts if supporting data is provided, and 35% will outright resist new concepts even when given supporting data.
Reduce carryback to prevent the need for workers to scrape material off the return rolls.
Additionally, there is no guarantee that the subjects are even paying attention.
• Safety equipment. When it comes to belt conveyors, the two primary pieces of safety of equipment are emergency stop switches and guarding.
Emergency Stop Switches
For emergency stop switches, the first thing you want to do is test the slack in the cable, which should not exceed 12 inches in length. Next, you want to check runout, which is the distance the belt travels after it is deactivated. There is not an agreed-upon figure for runout, since it is highly variable, based on whether the conveyor is inclined, declined, or level, if there is material on the belt, and the speed of the belt. Remember that emergency safety switches don’t stop the conveyor – they de-energize a conveyor, and then there is runout before the belt stops.
For emergency stop cables, they should 36 to 60 inches above a walkway, and the cables are required to be no longer than 164 feet. They also should be supported every 19.5 feet.
Guarding
When used properly, guarding is a very effective way to keep workers safe. First, make sure that your guards aren’t hazards themselves. They should weigh no more than 50 pounds, have no sharp edges, and if they have hinges, they should not create any pinch points.
Workers should be taught to never reach around, under, through, or over a guard. To remove a guard, it must require the use of a tool. Also, use an American National Standards Institute-certified guard gauge to determine if guards are the proper distance from the hazard.
We recommend painting your guards a color that helps them stand out from the equipment. However, that can make it difficult to do visual inspections of the equipment. Our recommendation is to paint the frame of the guard yellow and the field black.
For return rolls, you must have a guard on every one that is less than 7 feet in elevation. Return rolls installed over walkways or roadways must be guarded with a catch basket no matter the elevation.
Eliminate Exposure
As discussed, there are flaws to all of the common approaches to belt conveyor safety. We have come to the conclusion that the only way to completely prevent injury from belt conveyors is to eliminate exposure to the hazard.
Exposure to moving belts occurs most often when workers are tasked with cleaning and housekeeping, so you want to make sure you are doing everything you can to minimize the need for workers to clean near operating belts.
Some tips include:
• Reduce carryback to prevent the need for workers to scrape material off the return rolls. There are technologies available to make sure material does not stick.
• Reduce dust around conveyor belts. Some culprits of dust accumulation are an over-reliance on skirting and improper belt support.
• Reduce spillage from a transfer point by addressing belt sag, keeping your wear liner maintained, and by sealing at the trough.
Tucker Scharfenberg, managing editor
To view the webinar at no cost, go to www.grainnet.com/beltconveyors...
