Six workers were injured Tuesday when a coal-dust silo exploded at this We Energies power plant near Milwaukee.

Folks in coal country usually think of coal-dust explosions as something that happens underground, and as one of the biggest dangers that coal miners face every day on the job.

But reports in the Milwaukee Journal-Sentinel and Wisconsin Public Radio explain that Tuesday’s blast was different. The silo, one of nine at the plant, is used to collect coal dust that accumulates from coal that is brought to the plant by train. The dust is compacted and, like coal itself, is burned for fuel. The Journal-Sentinel’s coverage included a cool graphic of the silo and how it is used.

On Wednesday, the U.S. Chemical Safety Board’s Chairman, John Bresland, issued a statement to underscore the explosion dangers from all kinds of industrial dust:

Despite the efforts of NFPA, OSHA, the Chemical Safety Board, and many others, serious dust explosions and fires continue to occur,’ Mr. Bresland said in the new video. ‘As CSB chairman, my commitment is to do everything possible to make these tragedies a thing of the past. Stronger, clearer regulations and more robust safety programs in industry will prevent most dust explosions – and save lives.

The board also posted a YouTube video:

A year ago this Saturday, a catastrophic dust explosion destroyed the massive packaging plant at the Imperial Sugar refinery in Port Wentworth, Ga., fatally burning 14 workers and injuring 38 others. It was hardly the first such disaster.

In a November 2006 study, the CSB identified 281 fires and explosions that killed 119 workers and injured 718 others. The CSB has urged the U.S. Department of Labor’s Occupational Safety and Health Administration to develop a comprehensive regulatory standard designed to prevent dust explosions. OSHA has not issued a standard, but has developed a program to increase enforcement of existing regulatory provisions.

This problem has been covered repeatedly by my friends at The Pump Handle blog, and was also the subject of a major “60 Minutes” expose last year.

Of course, coal dust in mining operations is subject to a separate set of regulations enforced by the Labor Department’s Mine Safety and Health Administration. But in my “Beyond Sago”series, I found that dust-related problems — a clear cause of some of the biggest mine disasters in U.S. history — are still a repeated problem in underground coal mining.

Will President Obama protect workers by getting tough on explosive dust issues? So far, he’s still waiting for the Senate to confirm his nominee for Labor Secretary, Rep. Hilda Solis, D-Calif.