VANCOUVER - The father of a gas-station attendant killed while trying to prevent a robbery is calling on British Columbia's workplace-safety agency to reverse changes to regulations inspired by his son's death.

Doug De Patie says WorkSafe B.C. opened the door to unsafe conditions for workers in 2012 when it amended a set of rules known as Grant's Law, named after his son Grant De Patie.

“I think they basically sidestepped the regulations, found a back door and made it possible, if not probable, for workers to be put at risk and be killed,” he said on Saturday.

The father made the comments four years and a day after the changes took effect. The B.C. Federation of Labour's Young Workers' Committee held an annual overnight sit-in Saturday outside convenience stores in Victoria and Vancouver.

Grant De Patie, 24, was dragged to his death in Maple Ridge, B.C., in 2005 after trying to prevent a gas-and-dash robbery of $12.30 worth of fuel. Three years later, B.C. became the first province to enact a regulation that required customers to pay for fuel before filling up.

The province also brought in rules to protect late-night workers that required employers to install protective barriers or staff more than one person on overnight shifts.

But in 2012, WorkSafe B.C. amended the late-night worker rules to allow companies a “third option” to avoid installing barriers and staffing multiple workers if they put in measures including surveillance cameras, a time-lock safe and a panic button.

“None of those administrative measures, we think, are enough to protect workers,” said B.C. Federation of Labour president Irene Lanzinger. “The government clearly put the interests of the business community ahead of the safety of workers.”

Al Johnson, vice-president of prevention services at WorkSafe B.C., said it's the employer's obligation to assess the risk and ensure protocols are in place to address it.

“The regulation is a performance-based regulation where we expect employers to ensure the health and safety of workers,” he said. “When it comes to violence, it's based on their violence risk assessment and then they have a number of options available to them.”

Johnson said in the early trials of barriers, they didn't prove to be effective for a number of reasons, including that they prevented employees from interacting easily with customers.

He pointed out that the regulation requiring pre-payment before filling up had not been amended and that it has greatly reduced gas-and-dash incidents in B.C.

The death of a Calgary service-station worker last year has prompted calls for a pay-before-you-pump law in Alberta.

B.C.'s Minister Responsible for Labour Shirley Bond didn't immediately respond to a request for comment on Saturday.

Caitlin Davidson-King, chairwoman of the B.C. Federation of Labour's Young Workers' Committee, said the annual rallies have grown in recent years and Saturday marked the first time an overnight sit-in was held in Victoria as well as Vancouver.

“The reason why we're asking for Grant's Law to be reinstated is because workers are vulnerable,” she said. “When they're alone at night, there are certain emergencies that might come up and there's nothing to protect those workers.”