Mining Publication: Technology News 519 - EZ-Up Curtain Stoppings: A Practical Solution for Directing Ventilation Airflows in Large-opening Metal/Nonmetal Mines
Supplying fresh ventilation air to dilute airborne contaminants such as diesel particulate matter, diesel and blasting fumes, and silica dust is vital to protect the health of underground mine workers. Stoppings and other control devices that are used to direct the required airflow to the active working areas are an integral part of the mechanical ventilation systems used in underground mines. Stoppings should be engineered for the pressure dynamics to which they will be subjected at the specific location where they will be installed. In addition, they should be designed for quick installation and minimal maintenance, and they must maintain their structural integrity when subjected to differential air pressures. Due to the size of the entries, stoppings in large-opening mines are difficult to construct and maintain. Flexible curtain stoppings in particular are prone to damage from blast pressures and from repetitive flapping due to varying air movement in these mines. The EZ-Up curtain stopping is designed primarily for use as a temporary or portable stopping, although test results indicate that it may remain durable for an extended time. The stopping can be constructed from a variety of fabrics, including standard mine brattice. For these particular tests, stoppings composed of two separate curtain materials were evaluated: (1) a high-density polyethylene woven fabric and (2) a string-reinforced polyethylene film and polyester fabric. The EZ-Up curtain stopping is manufactured with a sewn-in loop so that it can be easily laced onto tubing while on the ground and then hoisted with a strap and ratchet mechanism system to the mine roof. Because the stopping is constructed mainly on the ground, miners exposure to the hazards of working at heights (typically 20-40 ft) associated with large-opening mines is reduced. The EZ-Up curtain stopping is constructed in four phases: (1) preparation and ratchet installation, (2) curtain preparation, (3) curtain hoisting, and (4) securing the perimeter.