At issue was whether Blue Mountain Resorts Ltd. should have reported the drowning as the province's Ministry of Labour demanded.
Both the Ontario Labour Relations Board and Divisional Court had previously found the drowning fell under the Occupational Health and Safety Act as a death or critical injury incurred by a person at a workplace.
The Ontario Court of Appeal disagreed.
"Sometimes a swimming pool is just a swimming pool," the Appeal Court ruled.
The incident arose in December 2007, when a guest drowned at an unattended pool at the resort in Collingwood, Ont.
The Labour Ministry took the view the incident was reportable. Blue Mountain said the pool was not a workplace and no workers were present when the drowning occurred.
In its decision — upheld as reasonable by Divisional Court — the labour relations board inferred that employees must have been present in the pool area sometimes to check and maintain it.
Accepting that logic, the Appeal Court decided, would lead to ridiculous results.
"(It) would make virtually every place in the province of Ontario — commercial, industrial, private or domestic — a 'workplace,' because a worker may, at some time, be at that place," the Appeal Court found.
"This leads to the absurd conclusion that every death or critical injury to anyone, anywhere, whatever the cause, must be reported."
According to the Ontario Snow Resorts Association, about 7,000 mishaps occurred at provincial ski resorts during the 2007-2008 ski season.
On a February weekend, Blue Mountain draws as many as 26,000 visitors, who average about 40 skiing-related incidents.
If the ministry's view was adopted, the Appeal Court stated, Blue Mountain could have to report each one.
Given that the act bars an employer from disturbing or altering an incident scene until an inspector gives permission, each incidents could force a temporary shut-down of one or more ski slopes.
The province's top court found the ministry's broader interpretation of the reporting provisions — aimed at protecting workers — to be patently unreasonable.
"Would parents have to report to the ministry if their child were injured at home because they had hired a nanny? Because hotel employees enter guest rooms, does a hotel room become a 'workplace' when a guest dies of a heart attack or a drug overdose or is murdered?" the Appeal Court wrote.
"There (must) be some reasonable nexus between the hazard giving rise to the death or critical injury and a realistic risk to worker safety at that site: There is no such nexus here."