What is a toy? Sure, tiddly-winks and Barbie dolls spring to mind, and it makes sense that toys like these should be covered under the tough new standards set down by the U.S. Consumer Product Safety Commission (CPSC) regarding the manufacture and testing of products marketed to children.

But what about model trains? Model train makers lobbied hard to be exempt from the new CPSC guidelines, arguing that the typical customer for their locomotives is not a child but a middle-aged man. The commission did grant this exemption, but it's still struggling to provide clarification about just what is and what is not a toy.

Take Halloween costumes. The Halloween Industry Association, for example, insists "thematic" costumes may not meet the definition because teenagers and adults like to get dressed up in costumes too. But does that mean that if an adult woman collects Barbie dolls that they too should be exempt?

The Handmade Toy Alliance has argued for exemptions on the grounds that adults are usually supervising when children use child-size instruments and craft tools. The Sporting Goods Manufacturers Association says footballs, lacrosse sticks and baseball bats should be considered "general use products" rather than toys, regardless of their size or the age of the user.

Under the Consumer Product Safety Improvement Act of 2008, the CPSC was assigned the task of defining a "children's product" — which includes such things as toys, clothing and household goods — and eventually enforcing the act. Among the regulations are more safety testing, additional recordkeeping and a reduction in the amount of lead that is allowed. But coming up with that definition has become so difficult that the commission has postponed votes three times.

A new vote is scheduled for today.

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