Death by nitrogen hypoxia, if cleared, would become the first new method of execution since the lethal injection was introduced in 1982. Nitrogen is a colorless, odorless gas that makes up 78% of the air inhaled by humans and is harmless when breathed with oxygen. However, the theory behind the new method is that altering the air to 100% nitrogen will cause a prisoner to pass out and die from a lack of oxygen. Alabama’s attorney general’s office told a judge that nitrogen gas will “cause unconsciousness within seconds and death within minutes." A state protocol said the gas will be administered for at least 15 minutes, or “five minutes after a flatline indication on the EKG, whichever is longer." Some US states are seeking new methods to execute prisoners because the drugs used in lethal injections are increasingly difficult to find. Alabama, Oklahoma and Mississippi authorized the use of nitrogen gas to execute prisoners, but the never-used method has faced stiff criticism. Much of the information in medical journals about nitrogen exposure comes from both the deaths of workers in industrial accidents & suicide attempts.