Many lives are devastated when a worker is killed on the job. Sometimes even entire communities. Take the case of four men, including three FFAW-Unifor members, killed when the fishing boat they were working last September foundered off the coast of Newfoundland. When word went out in the small community of Shea Heights near St. Johns that the Pop's Pride fishing boat had been lost on Sept. 6, the community with historic ties to the sea immediately felt the loss, even as residents clung to hope.

(Photo: John Sylvester via Getty Images) "Those community members, they're our family, they're our friends, they're our loved ones, and like anybody in any community across the country, you're going to hold out hope," Melissa Earles-Druken, chair of the Shea Heights Community Board, told reporters at the time. Any such hope diminished as the boat was found flooded, and two bodies were pulled from the water. The rescue efforts at that point officially switched to recovery of the remaining bodies, which have never been found. Families and the community were left to search for answers about what happened. Across Canada every year, we search far too often for answers to explain why and how our loved ones die on the job -- whether the sudden loss of an industrial accident, or the slow death from chemicals or other toxins in the workplace. In 2015, the most recent year for which numbers available, 852 workers died at work.

(Photo: Hill Street Studios via Getty Images) No worker should ever leave for work in the morning never to come back. No family should receive the devastating call that their loved one isn't coming home. And no workplace should have to continue living with the loss of a co-worker from a death that the employer could have prevented. It is for that reason that every year on April 28 Unifor, along with Canada's labour movement, marks the National Day of Mourning for workers killed or injured on the job. It is the most somber day of the year for workers and the labour movement. Across Canada, unions and labour councils hold ceremonies to mark the day. This year's Day of Mourning recognizes 25 years since the devastating events at the Westray Mine in Nova Scotia's Pictou County, in which 26 coal miners lost their lives in a series of explosions in the mine, less than a year after it was opened with great fanfare. The methane gas and coal dust explosions on the morning of May 9, 1992, are believed to have killed all 26 miners almost instantly, and came after safety concerns had been raised at the mine since its opening the previous September.