Gather your supplies. Wash your hands with soap and water for at least 20 seconds. Lay your baby on their back, hold the end of the NG tube with the open hole at the end of your child's nose. Reach the tube to their ear lobe, and then to the middle of their abdomen, holding it down in all three places. Wrap a piece of tape around the tube where it lies in the middle of their belly to mark the spot. Place a skin guard on your baby's cheek. Place water soluble lubricant on the end of the tube with the open hole, insert the tube into your child's nostril. Keep pushing the tube in until the piece of tape reaches the tip of their nose. Tape the tube to your child's face on top of the skin guard. Attach a syringe to the other end of the tube by twisting it closed. Slightly pull up on the plunger until there is a small amount of fluid in the syringe. Remove the tube from the tip of the syringe. Squeeze the fluid from the syringe onto a pH test strip. Match the color of the strip to the corresponding pH level on the chart. The tube is correctly placed if the pH is five or less.