CHARLESTON, W.Va. -- Only one out of every 25 machines used in underground coal mines across West Virginia is equipped with proximity detection systems that can help prevent some of the most common deaths and injuries in the mining industry.Seventy-four pieces of underground mine equipment were reported to have these systems, the state Office of Miners' Health, Safety and Training found in an August survey.That's about 4 percent of the 1,800 continuous mining machines, roof bolters, scoops, shuttle cars and other mobile equipment in use in West Virginia mines, according to the figures.Proximity detection systems shut off fast-moving mobile equipment when miners get too close to it, preventing miners from being crushed or pinned by the equipment.Eugene White, director of the mine safety office, said the numbers may have increased since his agency did its count in August, as mine operators anticipate the eventual finalization of a federal rule to require proximity devices."I would fully expect that number to be up," White said. "That number will go up."In addition to the 74 pieces of equipment with proximity detectors, mine operators have installed blind-spot cameras on 86 pieces of underground equipment, according to the state survey.Some industry officials have promoted cameras as an alternative to proximity detectors.But in its proposals for nationwide rules, the U.S. Mine Safety and Health Administration would mandate the use of proximity detection systems, not cameras. The National Institute for Occupational Safety and Health has cautioned that cameras can be a challenge in underground mines because of "poor lighting, dust and the extreme difficulty in keeping the cameras clean." Also, proximity detectors shut off equipment automatically. With cameras, equipment operators still must see fellow workers on the screen and take action quickly enough to prevent a collision.Between 1984 and 2010, 30 miners died and 200 were injured nationwide when they became crushed, pinned or struck by continuous mining machines underground, according to the U.S. Mine Safety and Health Administration.On the federal level, MSHA has been working on two rules to require proximity detection systems nationwide. One proposal, covering only continuous mining machines, is stuck inside MSHA. The other, addressing all other mobile underground equipment, has been pending at the White House Office of Management and Budget for more than two years.In West Virginia, state mine safety officials at one point hoped to move to require proximity detection systems ahead of any federal mandate.The state's Mine Safety Technology Task Force began studying the issue, in part based on a request from the West Virginia Coal Association, and planned to have a draft regulation ready by January 2009. And in September 2008, four top state mine inspectors drafted a memo recommending specific language that would have given mine operators a year to install the equipment.But the effort stalled, and the task force voted in September to resurrect its proposal following a Gazette story in August that detailed the previous recommendations and noted the state had never moved forward.Last month, industry members of the state Board of Coal Mine Health and Safety rejected the task force recommendation and blocked several similar proposals to move forward with a rule to require West Virginia mine operators to install proximity detection systems.At that Oct. 3 meeting, White told board members that his agency's survey found that more than 150 pieces of equipment statewide had either proximity detection or cameras."There are a lot of companies acting on their own," White told the board. "This is a work in progress."Board members did not ask White for a figure on the total number of machines in use, or inquire about what percentage of machines had either safety device. Last week, White provided those numbers in response to a request from the Gazette.Reach Ken Ward Jr. at firstname.lastname@example.org or 304-348-1702.