WASHINGTON, DC—The Department of Health and Human Services issued a series of guidelines Monday designed to help parents curtail their children's boundless imaginations, which child-safety advocates say have the potential to rival motor vehicle accidents and congenital diseases as a leading cause of disability and death among youths ages 3 to 14.

Jill Tyn, 4, perilously close to danger.

"Defuse the ticking time-bomb known as your child's imagination before it explodes and destroys her completely," said child-safety expert Kenneth McMillan, who advised the HHS in composing the guidelines. "New data shows a disturbing correlation between serious accidents and the ability of children to envision a world full of exciting possibility."

The guidelines, titled "Boundless Imagination, Boundless Hazards: Ways To Keep Your Kids Safe From A World Of Wonder," are posted on the HHS website, and will also be available in brochure form in pediatricians' offices across the country.

According to McMillan, children can suffer broken bones, head trauma, and even fatal injuries from unsupervised exposure to childlike awe. "If your children are allowed to unlock their imaginations, anything from a backyard swing set to a child's own bedroom can be transformed into a dangerous undersea castle or dragon's lair," McMillan said. "But by encouraging your kids to think linearly and literally, and constantly reminding them they can never be anything but human children with no extraordinary characteristics, you can better ensure that they will lead prolonged lives."

Although the exact number of child fatalities connected to an active imagination is unknown, experts say the danger is very real. According to a 2006 estimate, children who regularly engage in imagination are 10 times more likely to suffer injuries such as skinned knees from mythical quests, or bruises and serious falls from the peak of Bookcase Mountain.

One of the HHS recommendations emphasizes increased communication between parents and children about the truths behind outlandish fantasies. "Speak with your children about the absolute impossibility of time travel, magical powers, and animals and toys that talk when adults are not around," reads one excerpt. "If this fails to quell their imaginations, encourage them to stare at household objects and think clearly and objectively about their actual, physical characteristics."

The HHS also discourages aimless playtime activities that lack a rigid, repetitive structure: "Opt instead for safe activities like untying knots, sticking and unsticking two pieces of Velcro, drawing straight lines of successively longer lengths, and quietly humming a single note for two to three hours."

But even these relatively safe activities can become imaginative, experts warn, without proper precautions. "Do not let children know that, for example, sailors and pirates untie knots," McMillan said.

Although no cure has yet been developed for childhood imagination, preventative measures can deter children from potentially hazardous bouts of make-believe.

"Many of the suggestions are really quite simple, like breaking down cardboard boxes or sewing cushions to couches so they cannot be converted into forts or playhouses," McMillan said. "Blank pieces of paper, which can inspire non-reality-based drawings, should be discarded unless they are used in one of our recommended diagonal folding and unfolding activities. And all loose sticks left lying in the yard should be carefully labeled 'Not a Sword.'"

Unfortunately, removing everything from a child's field of view that could stimulate his active young mind is extremely time-consuming, and infeasible as a long-term solution, McMillan acknowledges. "To truly protect your children, you must go to great lengths to completely eliminate their curiosity, crush their spirit of amazement, and eradicate their childlike glee. Watch for the danger signs: faraway expressions, giggle fits, and a general air of carefree contentment."

Added McMillan: "Remember, if you see a single sparkle of excitement in their eyes, you haven't done enough."