If it wasn’t clear last week, it certainly is now. The Obama administration plan to “End Black Lung: Act Now” may not include a lowering of the legal limit for coal dust that causes the deadly disease.

Labor Secretary Hilda Solis just issued her department’s new regulatory agenda, listing the changes in federal rules that the Obama administration plans to be working on over the next few years.

Among the featured items is this:

Notice of Proposed Rulemaking on Reducing Coal Miners’ Exposure to Respirable Coal Mine Dust

MSHA plans to reduce miners’ exposure to respirable coal mine dust which causes “Black Lung,” to protect coal miners, and promote the Secretary’s good jobs for everyone policy.

MSHA plans to publish this proposed rule change by September 2010.

But, the wording has changed in a pretty significant way from the rulemaking item issued by the Obama administration back in May.

That proposal (calling for a proposed rule to be published in April 2012 2011) was titled:

Occupational Exposure to Coal Mine Dust (Lowering Exposure Limit)

Today’s announcement, though, is titled:

 Occupational Exposure to Coal Mine Dust (Lowering Exposure)

That’s right … the word “limit” is gone. And that’s significant.

Why? Six months ago, Solis told miners, the coal industry and the public that her agency was going to lower the limit. Now, lowering the limit is just one of several options that are being considered.

MSHA chief Joe Main and one of his top staffers, Dr. Greg Wagner, are clearly working on a plan they think will end black lung by lowering exposure to coal dust without actually lowering the Permissible Exposure Limit, or PEL.

Their thinking is outlined in this “Fact Sheet” issued along with today’s announcement. First, they list these key issues:

— Consider recommendations in the NIOSH Criteria Document and the Secretary’s Advisory Committee on the Elimination of Pneumoconiosis Among Coal Mine Workers including the recommendation to reduce miners’ exposure to respirable coal mine dust.

— Consider aspects of two previous proposals that would require an underground coal mine operator to verify the effectiveness of a mine’s dust control plan, and would allow MSHA to use a single, full-shift sample, as opposed to the average of five samples (existing requirement), to determine miners’ exposure to respirable coal mine dust.

— Develop a Quantitative Risk Assessment to identify the health risks to miners associated with current exposures and to project the risk reductions.

— Estimate costs and benefits under the proposed rule.

And this background:

Excessive exposure to respirable coal mine dust can cause coal workers’ pneumoconiosis and other diseases such as emphysema. These diseases, collectively known as “Black Lung,” are irreversible, cause substantial disability and can be fatal. These health hazards are pervasive in coal mines, both large and small. While considerable progress has been made in reducing dust levels in coal mines, miners continue to develop Black Lung from exposure to coal mine dust. Here are some key facts:

— MSHA’s coal dust regulations were last updated in 1980, but the current exposure limit of 2.0 milligrams per cubic meter (mg/m3) has been in effect since 1972.

— In September 1995, the National Institute for Occupational Safety and Health (NIOSH) recommended actions to lower miners’ exposure to respirable coal mine dust.

— In February 1995, the Labor Secretary convened an advisory committee to assess the adequacy of MSHA’s current program and standards to control respirable dust in underground and surface coal mines, as well as ways to eliminate Black Lung and silicosis among coal miners.

— Recent NIOSH data indicate an increased prevalence of coal workers’ pneumoconiosis “clusters” in several geographic areas, particularly in the Southern Appalachian Region. Recent NIOSH data also indicate that younger miners are showing evidence of advanced and seriously debilitating cases of coal workers’ pneumoconiosis.

Here’s my video again of Joe Main explaining why he believes MSHA may be able to end black lung without reducing the legal exposure limit: