Omega Block products are composed of non-toxic incombustible materials whose air permeability and relative fire-resistance characteristics are unequaled. Fully approved for constructing underground ventilation devices by MSHA, Omega Blocks reduce labor because they cover the area of 3 normal concrete blocks. Omega Blocks are easy to use because they can be accurately cut to size with a handsaw. A typical brattice stopping is dry stacked using alternating courses and then sealed with an approved sealant about the roof, rib and seams.
NIOSH contacted Burrell Mining Products to assist them develop ventilation solutions for large opening mines with cross-sectional areas exceeding 1000 ft². The primary goal was to improve air quality by reducing diesel particulate matter exposure (DPM) in the underground mine environment.
When developing a viable solution to the stated objective one must consider the inherent problematic issues associated with underground stone mining; large cross-sectional areas and the methods of extracting the mineral. Large vertical heights and widths lead to stability issues when constructing structures and repetitive production blast overpressures causing wear and tear damage. Newly promulgated air quality standards required existing mines to improve their air quality when ventilation was not a major part of underground stone mining planning. These mines ventilation plans had to be retro-fitted to meet the new standards.
The strategy taken for reducing underground DPM exposure was to increase air quantity and direct it to the problematic areas within the mine. Once the DPM is diluted, it is then carried away. Directing the increased air quantity via a series of permanent stoppings eliminated meandering and recirculating issues thus increasing the effectiveness of the ventilation system. Smoke and fumes from welding operations, suspended silica dust as well as annoying conditions such as fog and inert dusts were also removed.
Burrell Mining developed a large Omega Block (Omega 443 Block) and construction protocol which would allow for a stable Super Stopping to be built which would be strong enough to withstand blast overpressures.