Ontario has cut high diesel exposure limits for underground workers by 70% after lobbying by unions and other groups.
Province labour minister Monte McNaughton announced the change from 400 micrograms per cubic metre to 120mg/cu.m. “These new rules will save lives by lowering the amount of harmful chemicals from diesel exhaust allowed in underground mines,” he said at a press conference.
In submissions on the law change, Ontario’s United Steelworkers and Centre for Research in Occupational Safety and Health (CROSH) at Laurentian University recommend a safe limit of 20mg/cu.m.
However, CROSH director Sandra Dorman said last year there was no safe level of exposure to diesel particulates.
“The particles are so very small that when you’re breathing they can enter into really the deepest parts of the lungs,” she said. “And when they get in the lungs and they make contact with the tissue they can create inflammation, so that’s one hazard with them.”
United Steelworkers’ Ontario health, safety and environment committee chair, Malcolm Mills said the province’s previous standard for mine diesel particulates was higher than in other mining jurisdictions.
“The levels currently allowed today are well above what is known to cause cancers, specifically lung cancers and bladder cancers,” he said.
Dorman said there was a solution to the problem.
“Within Sudbury there are tonnes of conversations around electric battery vehicles and one of the primary reasons is because that can be part of the solution to reducing diesel,” she said.
