Test your instructions as thoroughly as your products

Oct. 20, 2011
A woman was permanently injured when her arm caught in the awning she used to shade her home deck

A woman was permanently injured when her arm caught in the awning she used to shade her home deck. She was following the written and graphical instructions provided by the manufacturer, which placed her in an extremely hazardous position that led directly to the accident.

Consumer products often come with instructions, warnings, and misinformation that lead to hazardous misuse of the products. Consumers should be able to turn to retailers for accurate product information, but, in most cases, retailers don’t know any more about the product than purchasers.

Manufacturers have a duty and responsibility to produce safe products. To accomplish this, all aspects of the product must go through hazard analysis and painstaking testing. One of the most-overlooked aspects of consumer products is their accompanying instructions and warnings.

A case in point: the aforementioned awning. The homeowners manually extended it when they wanted to use their grill, then collapsed and pivoted it into a storage position against the house when they were done. The manufacturer had outfitted the large, heavy structure with a strong spring system to minimize the force the homeowner had to exert to extend or store the awning.

The awning instructions included photos and drawings to demonstrate the storage procedure. They instructed the user to place his or her arm between two rods to get a stronger grip on the structure as he or she raised it to its stored position.

When the accident happened, the homeowner had placed her hand as instructed, but her hand slipped and got caught in the scissors action of this mechanism. The strong springs lifted her off her feet where she dangled for over 10 minutes until a neighbor rescued her. The accident damaged the nerves in the woman’s arm, leaving her with only partial use of the limb.

The manufacturer had never done a hazard analysis on the extension and storage system. In fact, it had only tested the storage procedure in a factory setting when creating the instructions and taking the accompanying photos.

The people who operated the awning during the instruction-writing and picture-taking phase were its designers and builders, all well aware of its idiosyncrasies. It did not occur to them to include language warning about the dangers of the scissor mechanism. This oversight left the company open to a suit from the homeowner which settled for a sizable sum.

Compare the approach of the awning manufacturer to that used by one of my former employers. Engineers there performed preliminary hazard analyses on many of the machines they built and used internally as well as the products they sold. They repeated the analysis on the first product manufactured using standard tooling.

When evaluating assembly and service operations and preparing the written manuals that would provide instructions on those operations, they asked people who had never even heard about the product to go through each operation step by step. One or more of the designers would take notes and sometimes videotape the person interacting with the product.

Due to this diligent approach, this company is seldom sued in product-liability cases. Its attention to detail makes it a risky target. MD

Lanny Berke is a registered professional engineer and Certified Safety Professional involved in forensic engineering since 1972. Got a question about safety? You can reach Lanny at [email protected].

Edited by Jessica Shapiro

© 2011 Penton Media, Inc.

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