Engineer David Chandler died after inhaling the gas at a brewery, an inquest heard.
About 250 competitors braved wet, cold and blustery conditions to take part.
His autistic daughter is being detained at a Northampton psychiatric unit.
Some 200 school leaders sign an 'open letter'
An independent investigation is now underway
England's Charley Hull finishes second at the KEB Hana Bank Championship in South Korea, three shots behind Chun In-gee.
Northampton Saints' European Challenge Cup campaign begins with a resounding home defeat by six-try Clermont Auvergne.
Northampton Chronicle and Echo
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