The Canadian Press

The broken scaffolding lies handing on the side of the building as Ministry of Labour officials investigate the incident, Friday, Dec. 25, 2009.

TORONTO — All four men killed after plunging 13 storeys when a scaffolding snapped on Christmas Eve were wearing body harnesses, but it seems three of the men were not using a lanyard to affix the harness to a solid structure, Toronto police said Thursday.

"The harness without a lanyard, even one with a lanyard but not attached, if it's not affixed to anything it's useless," said Det. Kevin Sedore.

Sedore said one man did have a lanyard, or lifeline, attached to his harness, but it was not connected to anything.

The revelation comes on the same day as construction and labour groups called on the province for an independent investigation into the accident. The Provincial Building and Construction Trades Council also called for a probe of what it called the construction industry's "seedy business practices."

The group said it did not know what training the four men, migrant workers employed by Metron Construction Inc., had received.

"Our training dictates your life depends on it -- don't go on a swing stage without the proper equipment," Mike Yorke, from the Carpenter's Union local 27 in Toronto, said as he pulled a large yellow safety harness out of a bag to demonstrate its use.

Both a full body harness and a lanyard tied to a lifeline are used to prevent falls, said Yorke, as he showed mechanisms on the harness that would lock to stop a fall.

"In the event of a quick failure or fall, it stops," Yorke said as he dramatically yanked at the harness. "That would've saved the workers' lives."

The tragedy could have and should have been prevented, said the council's Patrick Dillon.

"The system as a whole failed these workers."

In an email, Metron president Joel Swartz said the company would not comment until all investigations are complete, but added his condolences are with the families.

The trades council called for an independent review of safety procedures, a change to legislation and a thorough examination of business practices. It said an investigator with help from an advisory panel could make recommendations based on the findings.

It also wants a review of the Occupational Health and Safety Act and the Workplace Safety and Insurance Act.

Dillon said requiring workers to have a "competency card," which shows they have some training, similar to what construction workers have in Quebec, could also protect employees.

On Wednesday, the Labour Ministry said inspectors would visit hundreds of construction sites this month to inspect scaffolds as part of an enforcement blitz.

The widow of one of the men killed has said she would like to see a full public inquiry into the deaths. But Labour Minister Peter Fonseca has ruled out a public inquiry.

"I am confident that we will get answers to those questions through those investigations and that inquest," said Fonseca, adding there is already a police investigation, a Ministry of Labour investigation and a coroner's inquest.

In a statement, Progressive Conservative labour critic Randy Hillier called the safety blitz "meaningless" given the safety concerns the labour groups expressed Thursday.

NDP leader Andrea Howarth has also called for an investigation.

"I think that no stone should be left unturned when it comes to getting at the root of not only this particular incident but the broader issues at play here in the province of Ontario in the construction industry," said Howarth.

Mourners were to hold a vigil Thursday evening just below the Kipling Avenue building to remember where the five workers fell. Aleksey Blumberg, 32, Alexander Bondorev, 25, Fayzullo Fazilov, 31, and Vladimir Korostin, 40, were killed in the tragedy.

A fifth man, Dilshod Marupov, 21, is the lone survivor and is in hospital.

A trust fund has been created to support the families of Aleksey Blumberg, Vladimir Korostin, Alexander Bondorev and Fayzullo Fazilov, who died in the scaffolding accident. Donations can be placed in the Tragedy on Christmas Eve trust fund at TD Bank, account 1076-6432077.