Warn More Than Once
 
Many manuals include a “safety page” in the front, with all needed product warnings in one place.  The idea is that anybody opening up the manual will see that page first, and be warned about any hazards associated with the product.  If people read manuals from beginning to end and word for word, that approach might be sufficient.  But that’s not how people use manuals.
 
Most people will use a manual to find a specific procedure or to answer a specific question.  That means they’ll either flip through the pages until they find what they need or use the index or table of contents.  Then they’ll go right to that page—and never even see the safety page.  
 
Now, there’s nothing wrong with having a safety page in the front—just don’t let that be the only location for warnings.  Instead, analyze each section of the manual and each procedure for operating or maintaining the product.  Will the user encounter a hazard that requires a warning?  If so, go ahead and repeat that warning wherever it’s needed.  That way, you increase the chance that your user will see important safety information.

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