Published in the August 2007 American Longwall Magazine

A new SCSR, currently undergoing testing at the National Institute for Occupational Safety and Health, plans to remove the hazard of "human error" by eliminating the changeover process of transferring from one SCSR to another.

"Our model will allow a miner to replace a used SCSR with another without having to remove their mouth from their mouthpiece," Technical Products Inc engineering vice-president Paul Chambers said.

"With older models, the miner has to take a deep breath and hold it while they transfer from one SCSR to another. Under duress, that is difficult to do. With Technical Products Inc's model, miners can continue breathing when transferring from one SCSR to a new one."

TPI has been able to develop its SCSR under a $614,482 research and development contract from the federal Centers for Disease Control and Prevention.

Only awarded in February, TPI has accelerated development and now has its product undergoing testing and certification. It expects to go commercial by the end of this year.

While TPI's SCSR allows a miner to change over without exposing themselves to potentially poisonous gases, TPI's model is also dockable, Chambers said. The model allows miners to simply replace a used oxygen canister with a new one.

While the dockable design is the dominant feature, TPI’s unique SCSR design is estimated to be 40% smaller and 40% lighter than comparable compressed oxygen models. "For miners having to wear SCSRs for an entire shift, this size and weight savings is quite appreciable," Chambers said.

Expired air is recycled through a scrubber that removes carbon dioxide. A compressed oxygen canister on the belt-mounted SCSR then adds additional oxygen as required.

Unlike present SCSRs which use chemicals to create oxygen and are activated through pulling a tab, the company’s respirator provides oxygen on demand.

"Since our design incorporates a demand regulator, the system will provide oxygen-rich air as soon as it’s opened and the miner breathes through it – there is no warm-up period," Chambers said.

TPI is also developing filtered self-rescuers which protect users from carbon monoxide (CO) environments. SCSRs protect users from any adverse breathing environment including oxygen depletion, CO and methane.

TPI's FSR is made from a new CO scrubbing filter that also weighs 40% less and is 40% smaller than comparable carbon monoxide FSRs. "It also lasts much longer than comparable CO FSRs and is less exothermic, meaning it operates at a lower temperature that makes it more comfortable to use," the company said.