Chemical Safety Board releases report on dust explosion

Chemical Safety Board releases report on dust explosion incident

Chemical Safety Board releases report on dust explosion incident

The U.S. Chemical Safety Board (CSB),
an independent federal agency charged with investigating industrial
chemical accidents, has released its final report, safety
recommendations and an accompanying safety video in regard to a fatal
combustible dust explosion that occurred at AL Solutions’ metal recycling facility in New Cumberland, West Virginia, in late 2010.

The report reiterates a recommendation that the Occupational Safety and Health Administration (OSHA) promulgate a general industry combustibledust standard, something the agency has been calling for since its 2006study on what the board says are preventable accidents.

The Dec. 9, 2010, explosion at the West Virginia facility, a miller and processer of scrap titanium and zirconium metal, killed three employees and injured one contractor.

The CSB says the West Virginia incident is one of nine serious combustible dust incidents that it has investigated since 2003. In total, the explosions and fires caused 36 deaths and 128 injuries.

Rafael Moure-Eraso, CSB chairman, says, “Preventable combustible dust explosions continue to occur, causing worker deaths and injuries. The CSB believes it is imperative for OSHA to issue a comprehensive combustible dust standard for general industry with clear control requirements to prevent dust fires and explosions.”

The CSB report notes that most solid organic materials, as well as many metals, will explode if the particles are small enough and are dispersed in a sufficient concentration within a confined area, near an ignition source. The CSB report emphasizes that even small amounts of accumulated
combustible dust can cause catastrophic damage.

The CSB investigation also determined that AL Solutions experienced a history of fatal dust fires and explosions.

Mark Wingard, a CSB investigator, says, “The CSB learned that the AL Solutions facility had fatal fires and explosions involving metal dust in 1995 and 2006 in addition to the 2010 explosion. Also, from 1993 until the accident in 2010, there were at least seven fires that required responses from the local fire department.”

The CSB also has produced a safety video titled “Combustible Dust: Solutions Delayed,” which details the process of milling and blending metal powder at the facility, which is pressed into dense disks called “compacts.” The video includes a 3-D computer generated animation showing how the accident unfolded at the plant.

In presenting the findings of the study, Johnnie Banks, CSB lead investigator, says, “As the metals were broken down during milling, the risk of a metal dust fire or explosion increased as the metal particles decreased in size. At AL Solutions a metal blender used to process zirconium was having mechanical problems that had not been adequately repaired. As a result, the blender was producing heat or sparks due to metal-to-metal contact.”

Wingard adds, “The National Fire Protection Association Standard for Combustible Metals, called NFPA 484, recommends specific practices for controlling metal dust, but AL Solutions did not voluntarily follow those guidelines, and there are no federal OSHA standards to enforce similar requirements. In its 2006 Combustible Dust Hazard Study, the CSB recommended that OSHA issue a combustible dust standard for general industry based on the current NFPA guidelines.”

In the video, Moure-Eraso says, “Had a national standard for combustible dust been in place in 2006—and if industry had followed the requirements—many of the severe dust incidents that followed, including AL Solutions, may have been prevented. The time is now for OSHA to take
action to prevent these tragic accidents.”

The CSB does not issue citations or fines but does make safety recommendations to plants, industry organizations, labor groups and regulatory agencies such as OSHA and the U.S. Environmental Protection Agency.