Grain elevators, mills, and storage facilities depend on hazard monitoring systems to provide safety to their facilities. Agricultural companies operating with the inherent safety concern of dust-related hazards face ongoing challenges when it comes to protecting their employees, facilities, and processes.

Challenges such as high employee turnover, failing to understand NFPA/OSHA regulations, and neglecting data that empowers preventive and predictive maintenance often impedes companies from achieving safety best practices.

According to Craig Froehling, Cargill’s director of manufacturing technology-Grain, Ports, Oilseed Processing, and Biodiesel, “Maintaining a high degree of process safety in an environment of high employee turnover can be aided by robust automation. By interlocking hazard monitoring systems to automatically shut down impacted equipment and bringing the process to a safe state, it simplifies training new employees on what to do when an alarm occurs.”

This article examines the requirements of NFPA 660 for grain companies, the impact of hourly worker turnover, and the role preventive and predictive maintenance serve in hazard monitoring safety.

NFPA 660 Chapter 21
In the grain industry, where combustible dust can trigger catastrophic explosions, NFPA 660 has streamlined safety requirements by consolidating six combustible dust standards into one accessible resource.

Chapter 21 specifically addresses hazards in agricultural handling and food processing facilities, such as grain elevators and grain mills. Additionally, it puts forth requirements for the monitoring of certain equipment, such as feeding devices, elevator legs, belt conveyors, and enclosed conveyors. Furthermore, it establishes the foundation for modern hazard monitoring equipment designed to mitigate the hazard of combustible grain dust through early detection of ignition sources, including hot bearings, belt slippage, and belt misalignment. Sensors that monitor temperature, speed, vibration, position, alignment, and equipment jams (plug chute sensors) detect specific points of potential failure in these common areas of concern.

To adhere to the requirements of Chapter 21, each facility must know its hazardous location classification, how equipment can help meet those mandates, and an assessment of what is needed for compliance with the NFPA/OSHA standard.

For instance, it requires dust-tight designs and monitoring systems to mitigate explosion risks, which have caused significant losses as evidenced by Purdue University data, which documents 289 grain dust explosions in the United States since 1995. Site assessments from industry professionals can help a facility gain a better understanding of how to approach hazard monitoring. Compliance with NFPA 660 is essential, yet it represents only the minimum requirement. Sensors must be correctly installed and integrated into daily operations to generate timely warnings or automatic shutdowns.

High Turnover
High employee turnover is a persistent challenge in the grain industry that erodes the effectiveness of hazard monitoring. The 2018-19 Agribusiness HR Review reveals that 37% of agribusinesses experience turnover rates of 10-20%, with 18% reporting rates above 20% turnover.

Hourly positions are essential for operating and maintaining monitoring systems. Workers need to understand data and system warnings to leverage the facility protection benefits that hazard monitoring systems offer. Understanding how to inspect and test sensors, to keep them in working order, is essential to maintaining hazard monitoring systems. Where there is turnover in hourly positions, they typically require a minimum of two to four weeks for replacement, this is compounded by the previously mentioned turnover rate. This added complexity often results in understaffed facilities and inexperienced workers handling complex equipment.

The 2018-19 Agribusiness HR Review also indicates that 76% of agribusinesses maintain onboarding programs, though only 55% incorporate job shadowing, which is vital for hands-on learning about monitoring systems. This situation fosters errors, such as misinterpreting sensor alerts, which can escalate minor issues into serious hazards including fires or explosions.

Manufacturers can address these shortcomings by supplying mobile alerts from their monitoring system, simplifying system interfaces, and providing ongoing manufacturing safety training. These initiatives ensure staff comprehend how to utilize monitoring systems for preventive and predictive maintenance, optimizing equipment performance.

Manufacturers can also provide training on systems and how they work to mitigate persistent risks, including combustible dust and equipment failure. Certified sensors in classified areas, such as those prone to dust or gas, must be installed to trigger warnings or shutdowns upon detecting trends within warning and shutdown parameter ranges. For instance, rub block sensors on bucket elevators can identify belt and pulley misalignments by detecting temperature increases.
When manufacturers partner with grain companies by providing training and monitoring system validations it creates a knowledge base with which facility safety can be firmly established.

Leveraging Preventive/Predictive Maintenance
Effective hazard monitoring extends beyond acquiring OSHA/NFPA 660-compliant equipment. Preventive and predictive maintenance helps grain companies get ahead of problematic equipment and allows a facility to spot problems before they arise.

Hazard monitoring systems engineered with safety in mind provide live and accurate data to enable insights into machine health. These initiatives ensure staff comprehend how to utilize monitoring systems for preventive and predictive maintenance, optimizing equipment performance.

According to McKinsey research, predictive analytics can reduce downtime by 30% to 50%, such efforts promote a safety-first mindset that safeguards workers and sustains productivity. Gradual increases in bearing temperature, conveyor slowdowns, frequent belt alignment issues, vibration outside of set parameters all indicate the need for remediation, and predictive maintenance.

By examining these performance trends, maintenance teams can avert unexpected shutdowns, enhancing efficiency and safety. Manufacturers can bolster this process by offering training modules, live safety sessions, and real-time data dashboards, empowering operators to act on insights and strengthening dynamic partnerships.

Conclusion
When facilities acknowledge the need for safer operations through NFPA compliance, predictive and preventive maintenance, and an expertly trained workforce, members of the grain industry can forge a genuine safety culture.

“Despite the challenges that ag companies face,” says Bob Reis, vice president of sales for Electro-Sensors Inc., “many industry-leading companies have installed hazard monitoring systems that exceed the NFPA’s minimum requirements and possess systems that meet industry best practices, including training programs with system manufacturers.

“These companies are on the forefront of safety practices in the grain industry,” he adds.

Matthew Renfroe is marketing manager for Electro-Sensors. He can be contacted at 952-930-0100 and mrenfroe@electro-sensors.com. For more information, go to electro-sensors.com/applications/hazard-monitoring.

References
AgCareers.com. “Agribusiness Workplace Trends: How Does Your Company Compare?” The Daily Scoop, 2018, https://www.thedailyscoop.com/....
McKinsey & Company. “Don’t Be Reactive, Be Proactive with Preventive and Predictive Maintenance.” Mitsubishi Electric, https://us.mitsubishielectric.....
National Fire Protection Association. NFPA 660: Standard for Combustible Dusts. 2024 ed., NFPA, 2024.
Occupational Safety and Health Administration. “Grain Elevator Explosion Chart.” OSHA Grain Handling, https://www.osha.gov/grain-han....
Purdue University. (n.d.). Dust explosions. Engineering. Retrieved September 8, 2025, from https://engineering.purdue.edu....