A correspondent recently contacted us with an unusual concern. He had read that breathing helium could rupture the lungs: hardly a peaceful death!
Helium is an inert gas and perfectly pleasant to breathe (though dangerous as it can produce unconsciousness without warning). Death occurs through lack of oxygen to the brain rather than a rupturing of the lungs. The process, properly managed, is completely painless, as confirmed by many witnessed accounts, including those by Professor Ogden in Canada and others (a few such links are provided below). Consequently we were slightly puzzled as to the source of such information.
A quick search of the Internet soon provided the answer. The media had picked up on some foolish examples such as persons at a party, or having fun making the voice change pitch, and breathing helium directly from the canister. This is exceedingly dangerous and can cause (completely unintentioned) death. The ‘rupture’ of aveoli (the small balloon-like sacs within the lungs) was caused not by helium, but by the pressure of the gas (any gas). Helium in party balloon canisters is compressed to about 260 pounds per square inch, so suddenly opening the gas jet in an irresponsible way can cause a fairly formidable pressure of helium. The other possibility is in diving, where a diver comes to the surface and gas in his or her lungs expands suddenly.
The concern over helium and self-euthanasia is not about gas pressure, which is easily regulated by sensible adults studying the method, but over manufacturers’ announcements that many of their cylinders are now supplied with a helium-air mix, which is unsuitable for self-euthanasia.
http://www.cganet.com/helium%20article.php
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1070864/
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3923352/
http://www.ncbi.nlm.nih.gov/pubmed/12198347
http://www.ncbi.nlm.nih.gov/pubmed/20216304
http://www.ncbi.nlm.nih.gov/pubmed/24501824
http://www.ncbi.nlm.nih.gov/pubmed/20211999
https://en.wikipedia.org/wiki/Suicide_bag
http://www.balloontime.com/contact-us/faqs/
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