“Since 2010, one miner was killed when a storage bin collapsed; another miner was killed when the concrete silo he was standing on collapsed,” US Mine Safety and Health Administration officials revealed in its latest safety alert bulletin.
“These deaths and several near misses are alarming,” they said.
To prevent further injury and death, all mines must examine their surface structures and rectify any hazards.
Specifically, MSHA is urging operations to check structures for signs of damaged, weakened or displaced structural elements; bulging or deformed bin sides or tops; gapped joints; cracked or broken concrete; corroded or fatigue-cracked metal; bent or buckling columns, beams or braces; loose or missing connectors; and cracked, broken or inadequate welds.
Structural elements should be inspected for a reduced load-carrying capacity; thinned or missing sections of beam or column webs or flanges; as well as corroded, rusted or flaked metal surfaces; and delaminated plywood or water-weakened wooden structures.
Material that has collected at the base of structures and horizontal beam flanges should be cleared.
The agency also reminded miners to look for damaged support columns, braces, anchor bolts and eroded foundations.
The discovery of a problem and making it right are two separate actions, so federal officials stress the importance of reporting all of the areas where an indication of structural weakness is found. Weaknesses can also be avoided by protecting lower elements of structures from mobile equipment damage and by minimizing and eliminating spillage.
MSHA reminded operators that structures should be designed and, where applicable, certified by a registered professional engineer.
Significant modifications should occur only after consulting with an engineer and all structures should be constructed to proper specifications by trained workers with good materials and correct construction.