A union representing 12,000 workers in Saskatchewan has blitzed the government with concerns over anticipated labour law changes.

Members of the Service Employees International Union-West have handed over thousands of protest postcards at the Saskatoon cabinet office.

Union president Barb Cape says there will be harsh consequences for workers if new labour legislation is passed too quickly.

She says both unionized and non-unionized workers need to have a more active role in the changes.

The government plans to overhaul 15 separate pieces of workplace-related laws in one omnibus labour bill that is expected to be introduced in the legislature this fall.

Cape says a three-month consultation with unions wasn't long enough.

"We have no problem with fixing essential services. We have no problem with reviewing labour legislation," she said Monday. "But we think it should be done in a more widespread, encompassing manner so that everybody gets a chance to be involved in the conversation."

Cape said there are a lot of people who still don't know how the changes would affect them.

"Young workers, marginalized workers just do not have the opportunity to participate in these labour changes, and they're going to be the folks most impacted by these, so ... our government needs to step back and really give them a chance to have their voice heard."

SEIU-West represents workers in health care, education, municipalities, community-based organizations and retirement homes.

In a speech earlier this month to a business audience, Labour Minister Don Morgan talked about possibly taking away a union's ability to fine members who violate codes of conduct by taking money off their paycheques. He also mused about relaxing rules so as to allow 10-hour work days instead of eight-hour days.

Some labour law changes must be made. The province was told to fix its essential services legislation after a court ruled in February that the law was unconstitutional.