A worker fatally injured at a northern Idaho mine last year was wearing an inadequate safety harness, federal officials said.

Brandon Gray, 26, was buried in rubble after trying to dislodge a jammed rock bin Nov. 17 at the Lucky Friday Mine. He died from his injuries two days later.

A report released Thursday by the federal Mine Safety and Health Administration found the accident at the underground silver mine near Mullan happened because managers failed to ensure miners were provided with the right kind of protective equipment.

Gray was employed by Utah-based Cementation USA Inc., which had been contracted by Hecla Mining Co. to do work on a shaft inside the mine. Company leaders at Cementation USA were still working on a response to the MSHA report, said president Mike Nadon.

“We saw a lot of errors in the report,” Nadon said.

The accident was among three in 2011 that prompted the federal agency to order the Lucky Friday Mine closed in January for some safety improvements.

Gray was injured when he and a co-worker, Jason Figueroa, were working on top of a pile of broken rock and it gave way, burying the two men. Figueroa was freed and treated at a hospital, where he was released later that day. Gray’s cause of death was listed as suffocation and mechanical compression.

“The accident occurred due to management’s failure to ensure miners were provided with the proper personal protective equipment when required to remove blocked material in the bin,” according to the report issued by federal mine safety investigators.

The two men were wearing harnesses attached to “self-retracting lifelines” that were designed for an unobstructed fall. When the material underneath the men gave way, they didn’t fall rapidly enough to trigger the lifelines to lock before the miners became buried in the rubble.

“Additionally, the miners didn’t receive the proper training to safely perform the task of removing the blocked material from the bin,” the report said.

The men also lacked training for working in confined spaces, federal investigators said.

Nadon countered that the lifelines were appropriate for “normal situations” and the broken rock in question had some “unusual characteristics.” He also criticized the mining safety agency for the amount of time it took to investigate the death and issue a report.

“It struggled to find blame,” Nadon said.