If you’re a grandparent, chances are you spend a fair amount of time with your grandchildren. Four million American children live in homes headed by grandparents, according to the U.S. Census Bureau, and millions more visit their grandparents’ houses on a regular basis.

Kids being kids, they’re practically destined to hurt themselves when playing–even more so during the wintertime, when playtime encompasses activities like sledding and running around in sub-freezing temperatures.

“Nine out of 10 grandparents take care of their grandchildren at some point during the year,” says Angela Mickalide, program director for the National Safe Kids Campaign.

With that in mind, follow these child safety tips and recommendations when you’re hosting your grandchildren this fall and winter.

Get Kids Ready for Cold Weather

Keep ’em warm: Dress kids in three layers of clothes before they head outside. Make sure they wear hats and mittens (warmer than gloves) to prevent frostbitten ears and toes. Sunscreen, with an SPF of 15 or higher, is also a must for people of any age, even in the winter.

Watch the footing: Teach grandkids to walk slowly and carefully on snowy sidewalks and to avoid walking on icy patches. Waterproof, insulated boots with rubber soles and treading are a must. Always keep your walkways clear of ice and snow.

Sled safely: Check equipment before using to make sure it is sturdy. Choose gentle slopes clear of rocks and trees. Children should sled sitting upright; lying down increases the risk of head and abdominal injuries. Safety helmets are always a good idea, too. And remember to supervise kids when they’re sledding, every time.

Say “time out”: Have kids come indoors periodically from winter play to warm up. Ask them how they’re feeling; be alert for signs of frostbite (white, frozen skin) and hypothermia (lowered body temperature characterized by shivering, confusion and dizziness). Have them drink plenty of water to prevent dehydration.

Child-Proof Your Home for Grandkids

Move the dangerous stuff: Store matches, lighters, cigarettes, medications and other dangerous household products out of reach, preferably in a locked cabinet. This includes items you might normally have readily in a purse.. All medications should be in child-resistant packaging.

Remove choking hazards: Hard candies and nuts are especially dangerous for young children, but look out for anything the size of a marble.

Practice fire safety: The risk of fire increases dramatically in winter months. Make sure your smoke detectors are in working order, with one installed on each floor.

Poison prevention: Carbon monoxide (CO) is a tasteless, odorless gas particularly dangerous to grandparents and kids. Make sure at least two CO detectors are installed and in working order.

“Children have rapid metabolisms, so they absorb CO quickly, and older people excrete it from their bodies slowly, so higher amounts stay in their systems longer,” Mickalide adds.

Watch the heat: Never leave kids alone in rooms with space heaters or lit fireplaces. Candles shouldn’t be placed on low tables or shelves that kids can reach.

This story was updated from an earlier version by Kathleen Ewald. It was originally published on realtor.com(r).