In the second half of their first year, babies start to get around on their own and develop better hand-eye coordination. They're eager to explore their surroundings with these new skills, but at times their curiosity and inexperience can be dangerous. A baby's risk of an accident resulting in airway obstruction — that is, choking or strangling — is particularly high during this time.

The three types of accidental airway obstruction are:

• Suffocation, which occurs when an object such as a plastic bag or soft pillow covers a baby's nose and mouth.
• Strangulation, which occurs when a string, ribbon or cord gets caught around a child's neck.
• Choking, which occurs when a small object or piece of food gets lodged in a baby's throat or windpipe.

First, learn how to recognize airway obstruction. When something partially blocks the windpipe, the cough or gag reflex usually clears it without assistance. However, you must act quickly if your child displays any of these signs, which indicate that the obstruction is complete or nearly complete and oxygen is not reaching the lungs:

• Stops breathing or crying
• Has a weakening cough that turns into wheezing or gasping
• Starts turning blue in the face

If you can see something blocking the throat, sweep your finger through your baby's mouth to remove the obstruction. If nothing is visible, do not stick your fingers in his or her throat. You may cause an object to become more deeply lodged.

If your baby is fighting for air but is unable to make any noise, you must act rapidly.

• Call or have someone else call for emergency medical help.
• Place your baby on your forearm, facedown with the head lower than the trunk. Support his or her neck and head by firmly holding the jaw and turning the head to the side. Use your body for additional support.
• If your infant is too large, lay him or her facedown on your lap, head lower than the rest of the body.
• Give up to five rapid blows between the baby's shoulders with the heel of your hand.

If your baby is still not breathing, begin cardiopulmonary resuscitation.

As your baby approaches the age of exploration, take these measures to prevent common causes of choking, suffocation and strangulation.

1. Choose soft, smooth-textured foods. Babies generally start eating a few solid foods, such as soft cereal and pureed fruits and vegetables, at about 6 months of age. You can gradually introduce a greater variety of foods, but stick to items that will soften or dissolve easily in your baby's mouth. It's fine to offer your baby small amounts of the same food the rest of the family is eating, as long as you chop it very finely, grind it in a baby-food grinder or overcook it enough to mash.

   Foods to keep off limits because they commonly cause choking in children younger than 3 include:

   • Nuts
   • Grapes, berries and raisins
   • Unpeeled fruit
   • Raw or undercooked vegetables
   • Stringy foods, such as celery, broccoli, squash and asparagus
   • Corn
   • Unripe fruit
   • Dried fruit
   • Candy and gum
   • Potato chips and popcorn
   • Peanut butter
   • Hot dogs and luncheon meats unless cut into short, lengthwise strips
2. Make sure your child's crib is safe. Babies spend a lot of time sleeping during their first year. To keep your child safe in slumber, make sure that:
   • The crib railings are no more than 2 3/8 inches apart and the crib sides are flush with the headboard and footboard.
   • The mattress fits tightly in your baby's crib with less than a 1-inch space on each side.
   • The plastic wrap from the mattress packaging is completely removed. If you want to use a mattress cover, select one that has a zipper.
   • The ties that attach the crib bumper are less than 6 inches long to prevent strangulation. As soon as your baby can pull up in the crib, remove crib bumpers, crib gyms and any other crib toys.
   • A diaper bag or cloth diaper caddy isn't hanging on the crib railings.

   If you travel often or work outside your home, your infant may be sleeping in several different cribs. Be sure to inspect your child-care provider's crib as well as any playpens or portable cribs your baby uses.

3. Be careful of cords, ribbons and strings. Babies tend to pull and grab at any rope or cord they can reach, so it's important to keep electrical, telephone and window-blind cords tied up and inaccessible. Loose window cords are particularly hazardous because they hang in loops that can easily get tightened around a baby's neck.

   Some styles of clothing, particularly mittens and coats with strings, pose a similar hazard. In general, make sure your baby's clothes fit properly — not uncomfortably tight, but not dangerously loose, either. An agile baby can wriggle out of a too-big shirt and have it twisted around his or her neck very fast. Also check your child's clothes for loose strings or strips of fabric. Never put a necklace or headband on a baby.

4. Keep an eye on your baby when he or she is lying facedown. Laying your baby facedown increases the risk of suffocation, as a baby's neck muscles may not be strong enough to hold up the head. Instead, place your baby on his or her back. If you give your infant "tummy time," you should be in the same room and both you and the baby should be awake.
5. Keep track of small objects. Most infants develop a pincer grasp enabling them to pick up tiny objects. Also, they begin to crawl at 9 months. Until you have a crawling baby, you may not notice the half-eaten cookies, lost game pieces and loose coins that find their way to your floor. Even with limited mobility, your baby will likely locate every item and try to place it in his or her mouth. Before you let your baby explore, check the floor for stray objects. Also look behind furniture and underneath cushions. Another important precaution: Store plants high and out of reach.
6. Choose safe, age-appropriate toys. Many toys come equipped with choke tubes to test whether the toy is safe for your child to use. You can also refer to consumer toy-safety guidelines to determine if the toy is safe for your baby to play with. As a general rule:
   • Don't let your child play with balloons or with marbles, coins, balls or other items smaller than 1 3/4 inches in diameter.
   • Make sure soft, squeezable toys do not become small enough to fit into your child's mouth when compressed.
   • Remove plastic wrapping and stickers from all new toys.
   • Make sure any decorations or small parts, such as wheels and buttons, are tightly fastened to the toy.
   • Teach older children to keep their toys with small parts separated from the baby's playthings. Show them examples of toys smaller than 1 3/4 inches in diameter and 2 1/4 inches long, which is the smallest size recommended for children under age 3.

If you're careful and alert, you can limit airway-obstruction hazards in your baby's environment. It's impossible, though, to anticipate every risk. That's why you also need to know the signs of airway obstruction and the steps to take if it occurs.