An inquest is underway into the 2010 deaths of 3 people at St. Mary's Villa in Humboldt. (City of Humboldt)

An inquest into the deaths of three elderly residents at St. Mary’s Villa in Humboldt, Sask., is underway.

Father Roman Schneider, Monica Washkosky and Gertrude Lukan died following a carbon monoxide leak in a wing at St. Mary’s Villa in December 2010.

Another 24 residents and seven staff were ill from the gas leak, which was linked to a malfunctioning heating and ventilation system.

The public inquest was called to examine the events surrounding the deaths.

Among the things under scrutiny is the medical cause of death and the manner of death. The coroner’s jury could make recommendations to prevent similar deaths in the future.

Coroner Alma Wiebe of Saskatoon is presiding at the inquest, which is being held in the city's Uniplex.

Tammy Morgan, a granddaughter of Gertrude Lukan, is among those who are following the proceedings and looking for answers.

"How do they not have a detector in that boiler room?" she asked CBC News. "It's a question I'd like to know."

The nursing home is operated by the Saskatoon Regional Health Authority.

The inquest began Monday and continues until Friday.