Preventing grain entrapment
May 2, 2011
Unlike other agriculture-related injuries and fatalities, those involving grain entrapment are continuing to trend upward, prompting the industry to search for solutions.
In 2010, there were a record-setting 51 grain-related entrapments and suffocations documented in the U.S., according to the Purdue Agriculture Confined Space Database, which Purdue University’s Agricultural Safety and Health Program has used to record incidents since 1978.
“We knew 2010 was going to be bad, coming off 2009. The crop was wet, and it had a low test weight. We anticipated it being bad, but we didn’t anticipate it being quite as bad,” said Wayne Bauer, safety and security director, Star of the West Milling Co. “The trend line is not getting any better. If anything, it’s deteriorating. That’s what we need to focus on: Why are those numbers deteriorating and how do we reverse it.”
From 2009 to 2010, there was an increase of 13 cases, or more than 34%. From the low of 18 cases in 2001, the increase has been more than 183%. The actual number of cases may be 20% to 30% higher because there is no comprehensive reporting system and employers are sometimes reluctant to report incidences.
Preventing such grain entrapments was the focus of a safety symposium at the GSI Group’s Burl A. Shuler Learning Center in Assumption, Illinois, U.S., in March. Speakers addressed topics ranging from grain conditioning and quality control to modification of existing sweep augers and training options for emergency responders.
“This is a real problem; we need to get serious about it,” Bauer said. “A lot of people say to me that this is probably the Achilles heel of the grain industry.” Increased entrapments
If there’s one positive in the numbers, Bauer said, it’s that the industry is doing a better job of saving people when they do get trapped. Prior to 2005, about 25% of people who were trapped were rescued. Now, more than 50% are being saved.
“We’re doing a better job of encouraging people to use a lifeline, and firefighters are getting more knowledgeable about the options to rescue someone,” Bauer said.
But the question remains, why are the number of entrapments increasing? For one, Bauer said, the nation is growing more corn, about 13 billion bushels compared to 3 to 4 billion bushels in the 1960s. The industry is also holding onto the corn longer, particularly since 4.5 billion bushels is headed to the ethanol industry.
As a consequence, grain is spoiling or getting out of condition. Poor quality grain will not flow as well, which may lead to someone entering a bin and potentially becoming entrapped.
“Grain conditioning is not rocket science,” Bauer said. “We need to clean the grain, dry it properly, cool it properly and monitor the temperatures.”
In the last 100 years, the size of grain bins has increased significantly from a couple hundred bushels to more than a million bushels. When a discharge hole stops flowing, there could be 100,000 bushels left in a 105-foot bin, Bauer said. Reclaim systems are not adequate for the larger bins.
“A lot of the problems we’re having are guys getting in the bins and trying to punch a lump through the reclaim system,” he said.
Other factors contributing to grain entrapments include a lack of attention to restraint systems and inadequate hands-on training, Bauer said.
“A 10-minute discussion in the break room is not training. You need to get out in a bin, show employees how to secure a lifeline, how to identify hazards, and how to build a restraining wall,” he said. “You need to invite the local fire department in or someone who could help in emergency response.”
Bauer said facilities are not using progressive discipline when violations occur.
“You can have the nicest safety policy in the world, but if you’re not enforcing it, then you don’t have a safety policy,” he said.
Problems also are occurring outside of bins, when they collapse and the grain spills. The average lifespan of a concrete bin is 50 to 70 years and for a steel bin 25 to 30 years. But that can vary due to the engineering design and the number of times a bin is cycled per year.
After 1980, the quality improved, Bauer said, but the number of cycles also increased. Some facilities are turning the bins 25 to 40 times a year, but many of the bins weren’t designed to turn that often.
“How do you determine the lifespan of a bin, and at what point do you stop using it or only fill it to 70% capacity?” Bauer said. “A lot of problems aren’t just happening because people are getting in the bins; some of the problems are happening outside of the bins. At what point do we get serious about working around those bins?” Seven solutions
Bauer outlined seven best management practices to prevent grain entrapment.
First off, stay out of the bin if possible; create a zero-entry mentality. This requires grain conditioning and quality control to minimize grain spoilage, as well as safer and more efficient reclaim systems.
If it is necessary to enter a bin, never do it alone, Bauer said. The outside attendant must be trained and focused on the entrant and have the means to summon help quickly, if needed.
The third practice is to never enter a bin untrained. That training should include hands-on aspects and should involve the entrant, the attendant and local emergency responders.
It’s also important to follow the entry permit. Take the time to identify all the existing hazards and personal protective equipment needed to perform the job safely. Conduct a hazard assessment, review the standard operating procedures and post the permit. Use natural ventilation, an aeration system and/or test the air with an air monitor to assure the entrant that the air is safe to breathe.
Perform a shutdown/lockout of the equipment before entering. This includes following proper lockout and tag procedures of all equipment involved in the storage, drying and material handling systems.
The sixth best management practice Bauer outlined is securing the lifeline properly. Maintain control of the lifeline; the lifeline is useless if it is not secured properly. A Class III rescue harness is best, Bauer said, because it has a ring in front for positioning and decent padding for support. Ideally, the system should provide an overhead anchorage point and a method to minimize slack in the line.
Lastly, be prepared for an emergency. Identify a competent, adequately equipped emergency response team that can respond in a timely manner. Many elevators are putting together a countywide rescue team, with half of the team coming from the elevator and half from the fire department. Responders are sprinkled across the county, so there’s someone who can get to the site quickly, and start stabilizing the situation until the rest of the team arrives.
As for cost, Bauer said a facility should anticipate spending about $150 per person for yearly training; $300 for a Class III harness; $375 for a bin entry kit; $500 to $3,900 for a cofferdam; $200 for atmosphere testing equipment; and $4,000-plus for rescue equipment for a six-person response team.
These best management practices need to come together with new design practices to be the most effective, Bauer said.
Changes are needed in reclaim systems, including the size and spacing of discharge sump holes, safer and more efficient sweep augers and unloading conveyors beneath the floor. Bauer said he would like to see sump holes bigger than 12 inches by 12 inches.
“We need decent sized holes to help the reclaim system be more efficient,” he said.
Other design changes should include larger top access doors, or even top panels that could pop out in the event of an emergency. The industry should also consider moving the access doors to make rescue easier.
Side access doors also need to be larger and should have a minimum 3-foot-by-3-foot work platform with handrails. Bauer said 18-inch steps are not acceptable and 24-inch round doors should be avoided. The doors should be offset from the unloading auger.
Restraint systems should include an overhead anchorage point and be able to secure and control lifelines.