"B" is for BREATHING. With the victim's airway clear of any obstructions, gently support his chin so as to keep it lifted up and the head tilted back. Pinch his nose with your fingertips to prevent air from escaping once you begin to ventilate and place your mouth over the victim's, creating a tight seal (Figure 1).

As you assist the person in breathing, keep an eye on his chest. Try not to over-inflate the victim's lungs as this may force air into the stomach, causing him to vomit. If this happens, turn the person's head to the side and sweep any obstructions out of the mouth before proceeding.

Give two full breaths. Between each breath allow the victim's lungs to relax - place your ear near his mouth and listen for air to escape and watch the chest fall as the victim exhales (Figure 2).

If the victim remains unresponsive (no breathing, coughing or moving), check his circulation