Medical marijuana may be legal, but the way some approved Canadian growers are producing their pot is not, say fire chiefs in the country's two most prolific weed-producing provinces.

More than 3,400 production licences have been issued to grow medical marijuana across Canada, two-thirds of them in Ontario and British Columbia.

Fire chiefs associations in those provinces say Health Canada's secretive permit process and refusal to bring in better regulations for growers put lives and health at risk.

"There's no instruction manual on how to build a grow op. So they give you this licence to produce, you know 100 plants or 75 plants, but they don't tell you how to do it safely," said Jim Jessop, the Niagara Fall's assistant fire chief who speaks for the Ontario Association of Fire Chiefs on the issue.

Jessop said he's walked into Health Canada-approved grow operations where the wiring was bad, volatile chemicals were improperly stored and, in one instance, a powerful hydroponic light ballast was starting to char the floor.

"I've actually had to remove children from one of them. It was so unsafe," he said.

Health Canada has refused to give locations of the grow operations to fire or police officials, citing privacy concerns.

When the federal agency issues a licence, the grower must abide by all applicable federal, provincial, territorial and municipal legislation, such as building codes and electrical hook-ups.

The issue of safety isn't probed on the Health Canada application, although a grower must give a detailed account on the form of security measures and how they will protect their crop from loss or theft.

Len Garis, chief of the Surrey, B.C., fire department, said his firefighters have stumbled upon nine legal grow ops in the city through the same process used to shut down illegal operations - either the home was using three times the normal limit of power or police have been tipped to a potential grow site.

"Four of the nine we disconnected anyway because they had no permit, the electrical systems were altered and (their system was) so shoddy that they weren't safe, so we shut them down," said Garis, who is also the spokesman for the Fire Chiefs Association of British Columbia on the issue of marijuana grow operations.

Both the Ontario and B.C. associations say they've lobbied Health Canada asking for help in improving safety.

"We sent a number of briefs to Health Canada, asking them to just do one simple thing, as a condition of permit, make sure that zoning, electrical safety, fire safety is all taken into consideration with these locations, prior to issuing the permit," Garis said.

David Thomas, with Health Canada, said their inspectors have the authority to conduct inspections for compliance.

"To conduct these inspections, Health Canada inspectors must have the occupant's consent to enter the dwelling-place or a warrant issued by a Justice ..." Thomas said in an email response to questions.

The associations argue allowing the legal operations to be inspected would be safer for the grower and those around them.

Jessop said he has met with federal government ministers and staff to explain the problem and ask for help.

"They've acknowledged that there's no process in place to teach people how to wire these buildings properly, how to vent them properly, how to make sure they're fire safe," Jessop said.

Trevor Bain, with Ontario's Office of the Fire Marshal, said Health Canada has said keeping the locations secret will prevent legal grow operations from being raided by criminals trying to steal their marijuana.

"I can understand the need to protect them in that sense," Bain said. "But at the same time what about the first responder, what about the neighbour? Shouldn't we have a system in place that protects everyone?"

Garis said Surrey firefighters have been called out to fires only to find themselves attempting to fight flames while they stumble through a maze of electrical wires in a smoke-filled grow-op. He said some crew members have been shocked by faulty wiring.

Those issued grow permits are either growing for themselves or for someone who needs medical marijuana to relieve the symptoms of their illness.

Jessop believes a license to grow should be treated like any other license, such as a hair salon, which would need approval before it's allowed to start operation.

"The federal government should not issue these licenses to produce marijuana until the local authorities have inspected the set up to make sure it complies will all municipal and provincial bylaws."

Thomas said Health Canada is trying to find a balance between helping seriously ill people and providing adequate regulatory control.

"The department is working with the Royal Canadian Mounted Police, as well as the Canadian Association of Fire Chiefs to determine how best to address the risks that may be posed by licenses grow operations."