[lolbullshit]

you can put a bucket over your head and pipe helium into it and that will work the same. this is a waste of money. its like insult to injury

[max_]

If you do it badly, you might end up with brain damage and not die at all.

The whole point of such devices is to make sure it's done properly.

[Freak_NL]

And not leave a nasty surprise for whoever inevitably finds you.

[BrandoElFollito]

You also need to stabilize your head and the while body so that you do not leave the bucket for a longer time (to ensure death).

I assume that helium would not have the alert effect CO2 has - similarly to nitrogen which is probably too Henry to just it with a bucket as you describe.