He said: "Currently the Act does not regulate substances on the basis that in some circumstances they may be harmful. Rather the Act applies only to substances with intrinsic properties such as flammability, corrosiveness, explosiveness, ecotoxicity or capacity to oxidise.
"As helium and other inert gases have none of these intrinsic properties, they are not at present subject to regulation under the Act."
Mr Smith also called for Minister of Consumer Affairs Simon Power to consider placing an age restriction on the sale of helium.
He also recommended that the gas be sold mixed with oxygen and only in a container with an irremovable restrictor valve.
Mr Power said he had ordered a report from his officials, but the coroner had yet to receive it at the time of releasing his finding.
Mr Smith said he accepted there was a limit to what could be done with reclassifying the gas, "however there will be no doubt in my view and growing concern that the general public will increasingly utilise a substance such as helium to end their life and therefore steps must be taken to control its distribution".
This is the second time in a week a coroner has taken the unusual step of making details of a suicide public.
Coroner Tim Scott released his findings into the death of 14-year-old Fielding teenager William Lucas because he believed it could deter others from taking their own lives.
Where to get help:
* Youthline: Support for young people and their families; youthline.co.nz, 0800 376 633
* Kidsline: Phone counselling for children aged 9 to 13; kidsline.org.nz, 0800 543 754 (4pm to 6pm weekdays)
* Whatsup: Counselling for children aged 5-18; whatsup.co.nz, 0800 942 8787 (noon to midnight)
* The Word: Questions answered about sex, life and relationships; theword.org.nz
* Depression Helpline: Counsellors who can find the right support for you; depression.org.nz. 0800 111 757 (8am to midnight)