for you by taking the equipment away after your death, Nitrogen is your only option that will show nothing at autopsy.
Safeguarding Your Will
As discussed earlier, the medical profession has long argued that suicide is usually the outcome of a psychiatric illness. This makes rational suicide a contradiction in terms. If a person wants to die - regardless of the context - then QED they were not thinking rationally.
Luckily, the law has never gone down the path of equating suicide with mental illness. Rather, the courts have found in a wide rang of cases where suicide is no indication of mental illness. To this end, the law refuses to see suicide as the outcome of mental illness. Indeed, some suicide notes have even been upheld as wills. Two birds with one stone as they say.