There are two methods of submitting a breath sample, depending on your state requirements. The most common is a simple blow, inhale, blow method that is like a deep exhale and inhale pattern that you would use during a doctor’s visit. The other is a straight blow method that requires a more forceful breath. If you are considering using a provider whose device requires a humming action while breathing, you should know that this blow pattern can be more dangerous and less reliable than straight forward breath samples.