Estimation of the frequency, severity and primary causative factors associated with injuries and fatalities involving confined spaces in agriculture

Steven M Riedel, Purdue University


Research was conducted to assemble data on the estimated frequency, severity and primary causative factors associated with injuries and fatalities involving confined spaces in agriculture. Data were collected by reviewing cases from previously conducted research, local and national media (both on-line content and print sources), and published reports. Based on a review of literature, no prior studies were found that either addressed the overall frequency, severity and causative factors of agricultural confined spaces or defined what clearly constituted an agricultural confined space. Studies on specific types of confined space incidents were identified, including those involving grain storage, manure storage, and grain transport vehicles. A total of 1255 cases were identified in the United States between 1964 and 2010 fitting the definition of an agricultural confined space, as defined by the Committee on Agricultural Safety and Health Research and Extension for the North Central Region (NCERA-197). Data were collected on factors related to these agricultural confined spaces, to include the following: type and classification of facility (i.e. commercial grain storage, OSHA-exempt dairy manure storage, etc), agent of injury (i.e. grain bin, above-ground manure tank, feed storage tank, etc), age and gender of victim(s), geographic location of incident, and severity of incident. Grain storage facilities accounted for 71.0% of cases, manure storage structures accounted for 10.5% of cases, agricultural transport vehicles accounted for 9.2% of cases, forage storage structures accounted for 5.7% of cases, and all other cases accounted for 3.6%. Grain storage & handling facilities and grain transport vehicles collectively accounted for 80% of all cases. Of these 1004 cases, 795 (79.2%) involved entrapment or engulfment in a flowing agricultural material. Of these 795 entrapment or engulfment cases, 543 (68.3%) involved metal storage bins. Males accounted for over 96% of all confined spaces-related cases and over 65% of all cases resulted in a fatality. Where age was known, the average age of a victim was 38 years, and youth under the age of 16 accounted for nearly 20% of cases. The data were limited by the lack of reporting requirements, especially for non-fatal cases, and in many instances, lack of comprehensive epidemiological information. Recommendations for education, engineering and enforcement were developed and include: Education: Continue and enhance the current surveillance and documentation program, in order to assess the efficacy of or innovative prevention efforts. This should include completion of: Additional on-site investigations of incidents of high risk such as those involving children and youth under the age of 16 and the use of grain vacuums.; Further analysis of the data to identify potential trends and patterns such as incidents involving unload or sweep augers and falls into or from confined spaces.; Additional statistical analysis of variables to better understand specific causative factors.; More in-depth studies of the relationships between out-of-condition grain and incidents of entrapment and engulfment.; Additional collection of data on the rescue strategies being used and the efficacy of each. Continue promotion of public awareness of grain handling hazards, especially when out-of-condition grain may be present. Special attention should be given to the Corn Belt region of the U.S. Identify critical work practices with regard to all agricultural confined spaces that would reduce injuries and fatalities if implemented. The NCERA-197 Committee is ideally positioned to address this issue. Develop evidence-based educational curricula for key high-risk populations such as exempt farm workers and children and youth under the age of 16. Develop a national education agenda to address the risks associated with agricultural confined spaces located on currently OSHA exempt agricultural operations and ensure a reasonable distribution of educational resources to rural educators such as Extension educators, Vocational Agriculture Instructors in secondary schools, and seasonal & migrant worker labor contractors. Conduct surveys of farm owners and laborers to explore attitudes and behaviors related to agricultural confined spaces. Special attention should be given to their beliefs and attitudes concerning the risks of entering an agricultural confined space. Develop a model curriculum for training of emergency first responders and employees who may be called to respond to an entrapment in an agricultural confined space. Engineering: Develop appropriate engineering standards and practices to enhance the safety of new agricultural facilities and equipment that incorporate confined spaces. Current confined space standards for general industry should be incorporated into these facilities. Develop structural designs for agricultural facilities that put controls in place to mitigate hazards, such as: Access to and egress from the structure; Structures and equipment configurations designed to reduce the need to enter grain storage structures to remove out-of-condition and residual grain.; Equipment or component (i.e. pumps) removal/retrieval without the need to enter the structure, particularly with manure storage.; Consistent multi-lingual warning signs, labels, decals and placards.; Enhanced ventilation (i.e. ASABE S607) for all confined spaces. Develop recommendations for retrofitting existing facilities containing confined spaces to reduce the risk of injury or death. If existing facilities cannot be economically retrofitted to comply with current standards, they should be removed from service. Enforcement: Enforce current provisions of the Fair Labor Standards Act that prohibit children and youth under the age of 16 from being employed to enter an agricultural confined space. Develop a mutually agreeable set of processes and procedures for exempt facilities to comply with that: Do not unduly burden the producer economically; Provide economic incentives for retiring obsolete and unsafe facilities that cannot be economically retrofitted.; Focus on farm family members under the age of 16. Explore the economic impact of applying the current grain handling and confined space standards to currently exempt agricultural facilities that have employees who might enter these spaces.




FIELD, Purdue University.

Subject Area

Occupational health|Agriculture|Agricultural engineering

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