Guidelines - Common Entries - Section 230 (c)(2)
Guidelines - Entries in common with the belt conveyor entry
In general, these guidelines will be used for evaluating Section230 (c)(2)requests to use entries in common with the belt conveyor entry:
- The belt conveyor is cleaned and maintained to minimize float dust in the common entries.
- Stoppings and regulators shall be arranged to reduce the quantity of air traveling in the common entries to a minimum for the effective ventilation of all affected areas of the mine, and to provide an intake air split as an escapeway from the face to the main air current.
- Fire protection shall be installed and maintained on all belt conveyors in compliance with appropriate Standards.
- An early warning fire detection system (CO or smoke) that meets the requirements of 30 CFR part 75.351 is required. Carbon monoxide (CO) or smoke sensors willmeet the federal requirements for CO or smoke fire detection systems. The spacing of the CO detectors shall not exceed 1,000 feet. The belt air velocity shall be a minimum of 50 fpm or CO /smoke sensors spacing shall be reduced to provide an adequate alarm time (not to exceed 20 minutes). The CO detectors shall be set to alarm at the lowest practicable setting and be positioned in the ventilation current to provide the most effective detection.
- The number of common entries shall not exceed three entries including the belt entry, except the number of common entries is not limited for room with alength of less than 600 feet.
- Development for common entries shall be designed to be at a lower ventilation pressure than the main intake escapeway.
If a condition develops that causes the belt and common entries to be at a higher ventilation pressure than the main intake escapeway, efforts shall be undertaken to immediately correct the condition. If the condition cannot practicably be corrected, the mine operator shall notify the Department of the condition, the specific cause, area affected, and the steps that will be taken to maintain the pressure in the belt and common entries at the lowest attainable level.
- When the belt ventilation current travels away from the working section, no ignition sources, except equipment necessary to maintain the escapeway and personnel carriers, will be permitted in the intake escapeway unless CO detectors are installed in the intake escapeway. Equipment operated in the intake escapeway shall be equipped with an automatic fire suppression system, or comply with 30 CFR Part 75.380 F4.
- CO detectors shall give an audible alarm over the mine communication system. The alarm shall indicate the conveyor belt flight where the alarm occurred. Both visual and audible alarm signals must automatically be provided at all affected working sections and at all affected areas where mechanized mining equipment is being installed or removed.