Agricultural and Biosystems Engineering Publications
Campus Units
Agricultural and Biosystems Engineering
Document Type
Article
Publication Version
Published Version
Publication Date
2018
Journal or Book Title
Journal of Agricultural Safety and Health
Volume
24
Issue
3
First Page
113
Last Page
126
Research Focus Area(s)
Occupational Safety Engineering
DOI
10.13031/jash.12552
Abstract
Grain entrapments remain a major concern in the grain industry, with 1,100 incidents documented since the 1970s. One particular concern is the ability of a victim to breathe while entrapped in grain. Anecdotal reports suggest that victims struggle to breathe when entrapped in grain to a depth that covers their chests, yet some evidence indicates that victims should be able to breathe normally as long as their airways are not blocked regardless of depth. The hypothesis for this discrepancy is that previously published experiments measured an active stress state in the grain, while a person breathing also experiences a passive stress state during inhalation. The passive stress is significantly larger than the active stress. The objective of this study was to measure the passive stress when pushing against grain, such as during inhalation, and compare it to active stress state measurements. An MTS Criterion testing machine, which is a force deformation testing device, was used to push a block horizontally against a column of grain and record the force and displacement during the movement. The measured passive stress was calculated from the force and displacement values and ranged from 9.4 to 11.0 kPa at a depth of 20 to 30 cm. These values are three to four times larger than previously published measurements of stresses at similar depths. This result indicates that the discrepancy between experimental results and anecdotal reports is most likely due to the type of stress state experienced in grain entrapment. Findings imply that the pressures on the victim‘s chest during entrapment are sufficient to cause breathing difficulties or crush/positional asphyxiation in some cases. A full-scale study is recommended.
Copyright Owner
American Society of Agricultural and Biological Engineers
Copyright Date
2018
Language
en
File Format
application/pdf
Recommended Citation
Issa, Salah F.; Wassgren, Carl; Schwab, Charles V.; Stroshine, Richard; and Field, William E., "Estimating passive stress acting on a grain entrapment victim’s chest" (2018). Agricultural and Biosystems Engineering Publications. 1112.
https://lib.dr.iastate.edu/abe_eng_pubs/1112
Included in
Agriculture Commons, Bioresource and Agricultural Engineering Commons, Ergonomics Commons
Comments
This article is published as Issa, Salah F., Carl Wassgren, Charles V. Schwab, Richard Stroshine, and William E. Field. "Estimating Passive Stress Acting on a Grain Entrapment Victim’s Chest." Journal of Agricultural Safety and Health 24, no. 3 (2018): 113-126. DOI: 10.13031/jash.12552. Posted with permission.