Forensic Engineering Investigation of a Machine Guarding-Related Injury

Jason McPherson

doi:10.51501/jotnafe.v40i2.853

Authors

Jason McPherson

DOI:

https://doi.org/10.51501/jotnafe.v40i2.853

Keywords:

OSHA, ANSI B11, Machine Guarding, Forensic Engineering, Standards, Safeguard, Point of Operation, Normative Reference, NFPA 79

Abstract

OSHA regulations and industry-accepted standards are intended to be used in conjunction to help prevent worker injury. Despite the aforementioned intention, a point of operation injury occurred to an employee while he was operating a hydraulic rotary bending machine. The machine had been retrofitted with a two-hand control device that was intended to act as a means of point of operation safeguarding. A forensic engineering analysis of both the electromechanical design and programmable logic code — combined with a performance and prescriptive requirement analysis — ultimately revealed flaws in the design of the electromechanical system and software design. It also demonstrated a lack of adherence to the applicable industry-accepted standards related to machine guarding. These factors led to the point of operation injury.

References

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