While the fabrication of the unit was completed Down Under, company spokesman James Rau told International Longwall News in a recent interview that its design was based on requirements outlined by US laws.

"With MineARC's Australian head office having over 12 years in the refuge chamber business, we already had an established research and development team ready to concentrate on the many design challenges that a coal refuge chamber presented," he said.

The company's Texas office, he noted, was initially established to focus on North and South America's growing metal/nonmetal market, an effort that has been fruitful for the group because of its mission to integrate value to operations through design.

"This focus on our existing core business led the US operation to play a support role for the development of the coal chamber," Rau said.

When the Aussie team began the design work, the latest in legislation and industry information was provided so that the unit could exceed the strongest requirement outlines currently known, those for the state of West Virginia.

"We decided as a business that we wanted to supply a chamber that would operate under a wide range of conditions and not specifically only for the West Virginia market," Rau said.

"However, it needed to meet the West Virginia certification as this is currently the only standard in place in the US and other states are looking at this certification for guidance in purchasing decisions."

MineARC's southern hemisphere counterpart also supplies a coal unit, but the customisation of design was not as it was for the US, which primarily focused on a reduced seam height, he noted.

"Australian coal mines are typically large with less people underground, and the coal unit can be sold at standard dimensions," Rau said.

"Within the US, we are going to adapt the chamber's dimensions to suit specifically what the customer requires."

He added that this will attract those operations seeking a unit made specifically for their needs, including mine design and risk management requirements.

Rau cited West Virginia's role in setting the regulatory bar for federal lawmakers, and the changes that could be made at that level because of the state's progress, but the industry's fear is a gap between the state and federal level.

"The concern for both manufacturers and coal operators is what discrepancies will exist between the state and federal level," Rau said.

"Understandably for coal operators, they do not want to spend large amounts of money on equipment that may in the future be deemed non-compliant by federal regulations.

"For refuge chamber manufacturers, it also presents issues as designs may need to be changed or further research and development undertaken to meet new regulations."

He cited some of those non-parallel rulings already in existence, such as the numerous variations between the West Virginia Emergency Shelter Standard (56-4-8) and the Mine Safety and Health Administration's PIB P07-03 on breathable air on duration, gas levels, chemical handling and airlock purging capabilities.

"It would seem to me that a single federal design requirement which is based on actual current technologies' capabilities and generally accepted standards from other industries already using similar technologies would simplify the process for all parties involved," Rau noted.

For now, MineARC is concentrating its coal unit efforts towards the West Virginia certification process and conducting human trials. It is also evaluating its patented hydromatically powered scrubber system currently featured in its coal chambers for permanent safe havens, a design that is economically sound for operators.

"[They will have] an inexpensive method of providing refuge for large numbers of occupants without the use of electrical power," Rau said.

"The modern-day refuge chamber market is a new and developing concept for the United States.

"It has become an arduous process for mining companies to decide which of the numerous products available will firstly satisfy their own requirements and secondly MSHA and/or West Virginia standards."

Because it wanted to develop a unit that would be operational in any state, not just for operations in West Virginia, MineARC took longer than its competitors to bring the design to the market table.

"I think that coal mines in states outside of West Virginia are often incorrectly looking to West Virginia and assuming that products certified under the West Virginia standard will be appropriate for their mines' conditions," Rau said.

"Manufactures have a responsibility to their customers to outline what standards their products meet and to explain fully under what mine conditions their product will function."