It’s never been done before. It’s possible it will never be used. But, only days ago, Oklahoma legislators voted to adopt the use of a nitrogen gas chamber if it should prove impossible to obtain the drugs needed to continue lethal injections. Far from dusting off their electric chair, the grotesquely nicknamed ‘Sizzlin’ Sally’ like Tennessee or following Utah’s lead by returning to the firing squad, Oklahoma lawmakers have resorted to an old method with a modern twist. Nitrogen is an inert gas similar in effect to gases such as halon and helium and works on the human body in a similar fashion, but without the increasing pain and suffocation inflicted by cyanide gas, for so long the standard method for gas chamber executions.

The gas chamber is nothing new as a concept. The first was used in Nevada in 1921 to execute Gee Jong and, while never as popular as the electric chair, the ‘coughing box’ was widely used in States like California, Arizona, Wyoming, Missouri and Mississippi. In its original incarnation the gas chamber always employed cyanide gas to kill a prisoner. At a signal from the prison’s Warden and executioner would work a lever mixing sodium cyanide with dilute sulphuric acid to create a lethal cloud of cyanide gas inside an airtight steel chamber. The prisoner, strapped into a metal chair inside the chamber, would then suffer terribly before dying of hypoxia, a form of oxygen starvation. After being certified dead and left to sit in the chamber for some time after death, the gas is pumped out into the open air, the body removed by guards wearing gas masks and rubber gloves and the entire chamber has to be decontaminated from top to bottom.

Most gas chambers were specially built by Eaton Metal Products of Salt Lake City, Utah. Some, like those once used in California and Missouri, have two chairs in case two inmates are scheduled to die together in what California prison officials used to call a ‘double event.’ Others, such as Maryland, Mississippi and Arizona, have a single chair. Neither type would require much conversion to deliver a lethal dose of nitrogen gas instead of the far more dangerous cyanide. An airtight chamber would still be needed to protect the execution team and witnesses from themselves being injured or killed, but existing facilities could readily be converted.

The gas chamber was by far the most expensive, complicated, difficult and dangerous form of capital punishment ever adopted in the US. The chamber and associated equipment are very specialized in manufacture and operation. Preparing the chamber for use and decontaminating it afterward are also both technically difficult and are done at considerable risk to both the execution team and the official witnesses. All gas chambers leak to some small degree and, if it were not for thorough pre-execution testing carried out prior to every use of a chamber. Once the chamber itself has been certified airtight and Vaseline has been smeared heavily around the edges of the viewing windows the chamber can be tested with the cyanide-and-acid mix.

View of the gas chamber used for executions inside

View of the gas chamber used for executions inside

The suffering endured by the condemned was also often hideous even when a gas chamber execution went as planned, which, unfortunately, was by no means guaranteed. Cases such as Leanderess Riley in California, Dennis Lawson in North Carolina, Jimmy Lee Gray in Mississippi and Donald Harding in Arizona were horrendous for the condemned and not much better for those having to witness these executions. But that was with cyanide, not nitrogen. Nitrogen has never been tried as an execution method and, if it is, it would be the first trial of a brand new method in the US since Texas delivered the first lethal injection to Charlie Brooks back in 1982.

So how, theoretically, would nitrogen gas execution work? Would it be any more humane (or less inhumane) than cyanide gas, the electric chair, the gallows, the firing squad or the old-style cyanide gas chamber? The short answer is, until an inmate actually dies by this method, we just don’t know, which doesn’t bode well for whoever’s turn it will be to become an unwilling part of penal history. New York didn’t know how to use their electric chair the first time round and the execution of William Kemmler was hideously botched to the point where George Westinghouse claimed the executioners would have done better using an axe.. Nevada nearly killed the official witnesses when executing their first inmate by lethal gas when the chamber leaked. The first lethal injections and, it must be said, a great many subsequent ones, have been botched in various ways.

The theory is that a human body doesn’t detect abnormal physical symptoms with nitrogen in the same way as it does with cyanide. So, theoretically, the prisoner wouldn’t experience the same pain and feeling of suffocation as so many have before in gas chamber States. If anything, they would experience either a brief high followed by quick unconsciousness or a progressive euphoria before passing out and then dying.

There are two ways in which the gas could be administered. One would be to strap them into a chair in the chamber and apply a face mask similar to those used for delivering other gases, such as oxygen or anesthetics. A pilot’s oxygen mask connected to a gas bottle and regulator would be a basic and effective form of delivery. The advantage of delivering so large a volume of gas directly into a prisoner’s lungs would be unconsciousness in less than fifteen seconds and death in a minute or two. Certainly far quicker and far less cruel than cyanide gas as is used today.

The other would be to simply replace the air inside a chamber with increasing levels of nitrogen. As the nitrogen levels increased and oxygen decreased, the prisoner would slip into unconsciousness in around one minute and be dead in around seven. It wouldn’t be much faster than using cyanide gas, but it would be far less painful and cause far less suffering on the part of the prisoner. It would still, however, require multiple executions using nitrogen gas before the execution procedure could be refined into a fully workable, standardized process.