I've done loads of searching here and elsewhere and haven't found a good explanation, but I'll keep looking. The reality is people die from 1-2g of SN without all the suicide prep. Loads of reports out there on it. The idea that we have to fast for hours, drink 20g+ of SN in a tiny bit of water, take all these meds beforehand, etc etc is just silly to me. I understand WHY it's recommended, we all want it to be fast and painless and relaxing, but I'm confused why people think all this prep is a requirement for death.
I'll keep looking around. Short of liquids/foods that negate SN (I think orange juice is one), I see no issue with a situation closer to those 1910 coal miners you mentioned. It will probably take longer to lose consciousness, but that's hardly a reason to say it can't be done. Thanks for your input :)