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Forensic Engineering Evaluation and Testing of Horizontal Intrusion Protection Equipment for Stand-Up Forklifts

Ben T Railsback, M.S., P.E. (NAFE 713S) | Richard M. Ziernicki, Ph.D., P.E. (NAFE 308F)


In 2004, a report issued by the National Institute of Occupational Health and Safety (NIOSH) evaluated a fatal standup forklift accident where a warehouse forklift operator was crushed against a rack beam after the rack beam intruded into the operator’s compartment.

One of the recommendations of the report was that “Manufacturers of standup reach forklifts should include vertical framing or posts at the rear corners of their machines, from the operator’s console to the overhead guard, to protect the operator from horizontal components entering the operator’s station.”

Other published studies have also recognized the risk associated with the hazard of a horizontal rack beam entering the operator’s compartment of a stand-up forklift. It has been previously reported that there have been at least 250 incidences of horizontal intrusion as of June 2008.

The ANSI B56.1 Safety Standard for Low Lift and High Lift Trucks has recognized such guarding as permissible since 1993, and almost all stand-up forklift manufacturers have made such guarding standard equipment. The evaluation is related to the fatal horizontal intrusion incident involving a Raymond standup lift truck (forklift), operated by a 44 year old male.

Published By


Journal of the National Academy of Forensic Engineers, June, 2016
2016