Question

A panel in coalmine produces 400 tonnes per day. The number of persons employed in each of the three shifts is 110, 130 and 120. As per CMR, the minimum quantity of air that needs to be circulated at the last ventilation connection of the panel in m$^3$/minute is

• A. 780
• B. 900
• C. 1000
• D. 2400

Hint:

Ventilation requirements in coal mines are critical for safety, and CMR ensures adequate air supply based on both personnel and production levels.

Answer 1

The Correct Option is C

As per the Coal Mines Regulations (CMR), the minimum quantity of air required for ventilation in a coal mine panel is determined based on the number of persons employed in the largest shift and the production of the panel. CMR typically requires a minimum of 2.5 m$^3$/minute per person in the largest shift, plus an additional 2.5 m$^3$/minute per tonne of daily coal production. The largest shift has 130 persons, so the air required for personnel is $130 \times 2.5 = 325$ m$^3$/minute. The panel produces 400 tonnes per day, so the air required for production is $400 \times 2.5 = 1000$ m$^3$/minute. However, CMR also sets a minimum baseline for air quantity, often around 1000 m$^3$/minute for such panels, regardless of the calculated value. Here, the production-based requirement (1000 m$^3$/minute) dominates, and considering standard CMR guidelines for a panel of this size, 1000 m$^3$/minute is the minimum required.
Thus, the correct answer is 1000.