What is the life expectancy for someone with an fev1of 34 percent?

This depends entirely on the cause of the reduced lung capacity, how well it responds to treatment, and whether there is a continuing cause of potential lung damage (like smoking). Discuss with your doctor.

While such a value is considered to be abnormally low, a prognosis cannot be formulated on an isolated test taken out of clinical context. The BODE index for COPD survival can be accessed at mdcalc.com, more information will be needed.