Hanging is one method used for suicide. It is one of the more popular and effective suicide methods.  The materials needed are easily obtained, even in a prison setting. Additionally, because hanging has been widely used around the world for judicial executions, there is a good body of documentation available about various aspects of hanging.
Types of hanging
There are three types hanging: short-drop hanging, long-drop hanging, and decapitation.
|Type||Drop height||Mechanism of death||Time until loss of consciousness||Time until death|
|less than long-drop||Strangulation, leading to cerebral hypoxia||~15 seconds||10-20 minutes|
|Long-drop hanging||5-8 ft (1.5-2.5m), see below||Acute spinal cord injury, leading to severe hypotension  ||<500ms||5-15 minutes|
|Decapitation||more than long-drop||Decapitation, global brain ischemia||~3.7 seconds ||1 minute |
The proper drop height for long-drop hanging is given by Britain's Official Table of Drops.
The rope should be sufficiently strong. According to an overview on capital punishment compiled by Steven D. Stewart, the prosecutor in Clark County, Indiana:
The rope, which is of manila hemp of at least 3/4″ and not more than 1 1/4″ in diameter and approximately 30 feet in length, is soaked and then stretched while drying to eliminate any spring, stiffness, or tendency to coil. The hangman’s knot, which is tied pursuant to military regulations, is treated with wax, soap, or clear oil, to ensure that the rope slides smoothly through the knot.
Several things can go wrong when carrying out a hanging, leading to injury rather than death, and resulting in extra suffering for the subject.
The suspension mechanism may not be able to bear the full force needed to break the neck, resulting in injury rather than death. This can occur because: 1) a weak rope was chosen, 2) the wrong knot was selected or it wasn't tied correctly, or 3) the overhead beam is too weak and it breaks.
In the tables that indicate the correct drop height for long-drop hanging, they assume that the rope and overhead beam are fairly rigid. If using expensive climbing rope, make sure it's not dynamic rope.
If the person is discovered before death occurs, and medical help is gotten quickly, the subject may have permanent neurological disabilities.  Be sure you won't be discovered until well after the hanging is complete.
A recent example in the news of a soft hang is the suicide of L'Wren Scott, the girlfriend of Mick Jagger of the Rolling Stones in 2014. Most accounts of her death gave very specific details of her technique. She hung herself with a scarf from a doorknob.
In this method, the person killing themselves by suicide loses consciousness due to loss of blood to the brain. This is similar to the effect of a martial arts fighter being held in a headlock. One will usually pass out in less than a minute. The actual death by asphyxiation can take as long as four more minutes.
It is likely that Aaron Swartz used this soft hang method in his 2013 suicide. The reports were that he was hanging from a window hinge.
David Foster Wallace committed suicide by hanging. His first attempt(s) failed. In his successful attempt, he had duct taped his wrists together, presumably to keep himself from involuntarily freeing himself due to survival instinct.
- Suicide by hanging#Prevalence on Wikipedia
- Rijn CM van., Krijnen H, Menting-Hermeling S, Coenen AML. Decapitation in Rats: Latency to Unconsciousness and the “Wave of Death.” Chapouthier G, ed. *PLoS ONE*. 2011;6(1):e16514. doi:10.1371/journal.pone.0016514
- Salim, Ali, et al. "Near-hanging injuries: a 10-year experience." *Injury* 37.5 (2006): 435-439.
Depending on the source, between 0% and 33% of patients admitted to hospital had permanent disability.
- Medalia, Alice A., Arnold E. Merriam, and John H. Ehrenreich. "The neuropsychological sequelae of attempted hanging." *Journal of Neurology, Neurosurgery & Psychiatry* 54.6 (1991): 546-548.