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One of the more important collapse modes for straight, combination, and extension ladders is base slide out; the top of the ladder slides down the support wall as the base slips away from it. Various fundamental models have been used to study this behavior. This paper revisits the analytical solutions associated with these models and describes their implications for the analysis, design, and testing of ladders.

When the handrail assembly broke away from a wooden deck attached to the rear of a private residence, the victim fell 12 feet to the lawn and sustained injuries rendering him a quadriplegic. Although the local building code required the handrail to withstand a 200 lb load applied in any direction at any point on the handrail, no guidance was given to the do-it-yourselfer who built the deck and railings to assure him that the final construction would produce an acceptable railing. The authors conducted testing and a statistical analysis of railing strength comparing the construction method used by the builder of the accident railing to another construction method utilizing a commercially available handrail bracket. The test program demonstrates that the strength of the wood used to build handrails can vary greatly and that a controlled method of building a handrail is necessary to ensure the integrity of a product intended to be consumer customized and assembled. It is necessary to have acceptable methods of railing construction because the failure of a railing joint can be life threatening. This is especially true in the consumer/do-it-yourself market where the designer/builder is not necessarily knowledgeable about building codes or construction methods. A commercially available handrail bracket known as Create-A-Rail® can provide the consumer with the guidance necessary to assure an acceptable handrail / post joint.