How long should one rescue breath last, and what is its purpose?

A rescue breath should last about 1 second, and its primary purpose is to make the chest rise visibly. This indicates that air is being delivered into the lungs effectively. The timing is crucial; a breath that lasts approximately 1 second allows for a sufficient intake of air without over-inflating the lungs, which can cause complications such as gastric inflation. When performing rescue breaths, the lifeguard should ensure that the recipient's chest rises and falls with each breath, confirming that the air is reaching the lungs. This method is an essential component of effective CPR, as it helps restore oxygen to the body during a critical situation when the individual is not breathing normally.