A national safety group is urging states and regulators to adopt new standards that would ban a pipe-cleaning practice blamed for a 2010 Connecticut power plant explosion that killed six workers.
The National Fire Protection Association's new standard, published a few weeks ago and publicly introduced Tuesday, prohibits the use of natural gas to clean pipes at industrial plants, commercial developments and other projects.
The standard is not binding, but could be used by state legislatures and the U.S. Occupational Safety and Health Administration to craft regulations banning the "gas blow" practice and encouraging companies to use nitrogen or other nonvolatile substances to clean pipes.
Connecticut this year became the first, and so far the only, state to outlaw the procedure, in which high-pressure natural gas is forced through pipes to push out metal shards, dirt and other debris.
National Fire Protection Association President James M. Shannon, who outlined the new procedure Tuesday at Middletown City Hall, said it usually takes a few years to develop new standards, but that the gas blow prohibition was put on a faster track because it could save lives.
The Chemical Safety Board, a federal investigative agency with advisory authority, has also asked OSHA to ban the gas blow procedure. OSHA officials have said they are considering the input, but as of Tuesday, had not issued a moratorium.
Six workers were killed in February 2010 when crews building the Kleen Energy Systems power plant in Middletown performed a gas blow.
About 400,000 cubic feet of natural gas and air was released in tight quarters, creating an explosive mixture large enough to fill a professional basketball arena. The ensuing blast was felt for miles and flattened much of the complex.
Investigators have not determined what ignited the gas and air mixture, though OSHA later said welders had been working nearby, and that gas and diesel heaters were left running during the gas blow.
Up to 50 people were injured, and lawsuits filed by the estates of the deceased workers and dozens of injured workers are still pending.
Crews had performed the same procedure eight days earlier with no problems, illustrating how unpredictable it can be and how the smallest factor can change everything, Middletown Mayor Sebastian Giuliano said Tuesday.
"The margin for error in these kinds of processes is paper-thin," he said.
Rosa DeLauro, whose congressional district includes Middletown, said Tuesday she felt compelled to honor the deceased workers by repeating each of their names so their deaths were not in vain.
"They're not just names or numbers. They have families, all of whom today are trying to adjust to their suffering and their loss," DeLauro said.
"We all feel very, very deeply that we owe it to the men who perished and their families and their colleagues ... to put such a standard in place," DeLauro said.
OSHA imposed $16.6 million in fines against the companies involved in the Connecticut blast. The two main construction companies, O&G Industries of Torrington and Keystone Construction and Maintenance of Rowley, Mass., are disputing the fines and their cases remain unresolved, an OSHA spokesman said Tuesday.
No criminal charges have been filed, but investigations by Middletown's police and fire departments remain open and the evidence is being protected for potential use at criminal and civil trials.
OSHA also has sent warning letters about the dangers of gas blows to companies involved in the 125 gas-fired turbine power plants planned or under construction.
Among other measures, the new National Fire Protection Association standard prohibits using flammable gas for pipe cleaning; requires crews to be sure that the substance released goes into a safe outdoor area where it will not build up; sets rules for alerting other workers; triggers crews to stop pipe-cleaning procedures under certain conditions.
Companies that follow the rules would use them not just at power plant construction sites, but all major projects ranging from new shopping malls to schools to industrial plants.
Workplace safety groups say forcing air, steam or nitrogen through pipes for cleaning is far safer than natural gas, but that natural gas has been particularly popular at power plants because it's already on hand _ and therefore less expensive than bringing in other materials and equipment for the pipe purges.
The Middletown explosion came as power generators are increasingly relying on natural gas to produce electricity because it's plentiful and cleaner than coal, and the use of gas is growing to power factories and heat homes.
Gas is used to make about one-fifth of America's electricity. That's expected to grow to 26 percent by 2018 as older, coal-fired plants are retired.