Choking Hazard
Never let children under the age of 7 play with a yo-yo unsupervised. Yo-yo strings and other parts pose a choking hazard if ingested. Many yo-yos light up and make noises, which means small screws, batteries and the lids to battery compartments can cause even more trouble for small children.
Sufficient Space
Make a mental note of your surroundings before attempting to perform yo-yo tricks. Check the area around you for people, animals and objects. You want an area that gives you at least a 5-foot clearance, depending on the length of your yo-yo, so you won't have to worry about harming anyone or knocking over breakables. Hitting your yo-yo off a shelf or wall could also cause it to ricochet and cause harm to your own body. Also be mindful if you're in a public place, such as a park or playground, where people might be walking by. Just because no one is around when you're starting your yo-yo tricks doesn't mean no one will come along later.
Water Yo-Yo Safety
The water yo-yo, a variation on the standard yo-yo, grew in popularity in 2003. Rather than a string attached to a spool, the water yo-yo involves a liquid-filled sack attached to a long rubber cord. It works on a similar principle to a standard yo-yo, in that it comes back to you after you throw it in a given direction. The water yo-yo can pose a choking hazard to young children. Not only can it block a child's airway if ingested, but it can also easily wrap around a child's throat. The consumer affairs department in Massachusetts found that particular brands of the water yo-yo could be made from toxic, flammable materials.