Fatality Alert - Fatality #12 - August 17, 2012

Accident Report: Fatality Reference: 
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METAL/NONMETAL MINE FATALITY - On August 17, 2012, a 58-year old equipment operator with 19 years of experience was killed at a cement operation. The victim was working on the roof of a 189-foot tall silo when the roof collapsed. Rescuers responded immediately and recovered the victim on September 4, 2012.

top view of a silo with its roof caved inward.
Best Practices: 
  • Routinely inspect the entire silo including walls, top, hopper(s), feeders, conveying equipment, liner, roof vents, etc. Look for structural damage, exposed rebar, stress cracks, corrosion, concrete spalling/cracking, signs of overfilling, top lifts, dust spills from seams during loading, damage to climbing devices, etc. The structure should be inspected by a professional engineer knowledgeable in silo design and construction.
  • Ensure a competent person conducts examinations to identify hazards.
  • If damage is discovered, prohibit use of and access on the silo and in the surrounding area until repairs are complete and/or a registered professional engineer has declared it structurally safe to use.
  • Modifications or equipment additions to a silo should be under the direction of a professional engineer.
  • Ensure process controls and dust collector baghouses are in working order to prevent overpressure, overfilling, or excessive vacuum. Dust leaving a silo may indicate structural damage or equipment malfunction.
  • Ensure aeration systems and other means of enhancing hopper flow are in working order so asymmetric flow patterns do not develop within the silo and damage the walls, hopper, and roof.
  • Provide silo level probes/weight measuring technology for /equipment to monitor silo material filling and discharge in the silo and keep it in working order.
Additional Information: 

This is the 12th fatality reported in calendar year 2012 in the metal and nonmetal mining industries. As of this date in 2011, there were 7 fatalities reported in these industries. This is the 2nd Falling Material fatality in 2012. There was 1 Falling Material fatality in the same period in 2011.