CALIBRATION CORRECTION CHART READING (fpm) CORRECTION READING (fpm) CORRECTION 50 + 15 500 - 5 75 + 15 550 - 8 100 + 14 600 - 10 125 + 14 700 - 15 150 + 14 800 - 20 175 + 13 900 - 25 200 + 12 1000 - 30 250 + 11 1200 - 35 300 + 10 1400 - 45 350 + 5 1600 - 50 400 1800 - 60 450 - 2 2000 - 65

Air Velocity = Reading + Correction CALIBRATION CORRECTION CHART Air Velocity = Reading + Correction READING (fpm) CORRECTION READING (fpm) CORRECTION 50 + 15 500 - 5 R = 600 75 + 15 550 - 8 1 R = reading on anemometer R = 620 fpm 100 + 14 600 - 10 C = - 10 1 125 + 14 700 - 15 C = - 15 150 + 14 800 - 20 2 175 + 13 900 - 25 R = 700 200 + 12 1000 - 30 2 250 + 11 1200 - 35 Interpolation Formula 300 + 10 1400 - 45 350 + 5 1600 - 50 400 1800 - 60 (C - C ) 450 - 2 2000 - 65 2 1 C = x (R - R ) + C 1 1 (R - R ) 2 1 ((-15) - (-10)) C = x (620 - 600) + (-10) = -11 fpm (700 - 600) Air Velocity = 620 fpm + (- 11 fpm) = 609 fpm

Medium Velocity Air Measurements (anemometers) CALIBRATION CORRECTION CHART A = W x H H + H + H 1 3 2 Average H = 6.2’ 5.8’ 18.7’ The dimensions of the mine entry were measured. READING (fpm) R = reading on anemometer R = 380 fpm CORRECTION READING (fpm) CORRECTION 50 + 15 500 - 5 75 + 15 550 - 8 100 + 14 600 - 10 125 + 14 700 - 15 150 + 14 800 - 20 175 + 13 900 - 25 200 + 12 1000 - 30 250 + 11 1200 - 35 300 + 10 1400 - 45 350 + 5 1600 - 50 400 1800 - 60 450 - 2 2000 - 65 Interpolation Formula C = (C - C ) 2 1 (R - R ) x (R - R ) + C Air Velocity = Reading + Correction q = V x A

Medium Velocity Air Measurements (anemometers) CALIBRATION CORRECTION CHART READING (fpm) R = reading on anemometer R = 380 fpm CORRECTION READING (fpm) CORRECTION 6.2’ 5.8’ 5.8’ 50 + 15 500 - 5 75 + 15 550 - 8 18.7’ 100 + 14 600 - 10 125 + 14 700 - 15 150 + 14 800 - 20 H + H + H 1 3 2 Average H = 175 + 13 900 - 25 R = 350 200 + 12 1000 - 30 1 250 + 11 1200 - 35 C = + 5 300 + 10 1400 - 45 1 350 + 5 1600 - 50 C = 0 400 1800 - 60 2 6.2’+5.8’+5.8’ 3 Average H = 450 - 2 2000 - 65 = 5.9’ R = 400 2 Interpolation Formula A = W x H = 18.7’ x 5.9’ = 110 sq.ft. C = (C - C ) 2 1 (R - R ) x (R - R ) + C q = V x A ((0) - (+ 5)) q = 382 fpm x 110 sq.ft. C = x (380 - 350) + (+ 5) = + 2 fpm (400 - 350) q = 42,020 cfm Air Velocity = 380 fpm + (+ 2 fpm) = 382 fpm

Medium Velocity Air Measurements (anemometers) CALIBRATION CORRECTION CHART A = W x H H + H + H 1 3 2 Average H = 3.5’ 3.4’ 3.3’ 20.2’ The dimensions of the mine entry were measured. READING (fpm) R = reading on anemometer R = 310 fpm CORRECTION READING (fpm) CORRECTION 50 + 15 500 - 5 75 + 15 550 - 8 100 + 14 600 - 10 125 + 14 700 - 15 150 + 14 800 - 20 175 + 13 900 - 25 200 + 12 1000 - 30 250 + 11 1200 - 35 300 + 10 1400 - 45 350 + 5 1600 - 50 400 1800 - 60 450 - 2 2000 - 65 Interpolation Formula C = (C - C ) 2 1 (R - R ) x (R - R ) + C Air Velocity = Reading + Correction q = V x A

Medium Velocity Air Measurements (anemometers) CALIBRATION CORRECTION CHART READING (fpm) R = reading on anemometer R = 310 fpm CORRECTION READING (fpm) CORRECTION 3.5’ 3.4’ 3.3’ 50 + 15 500 - 5 75 + 15 550 - 8 20.2’ 100 + 14 600 - 10 125 + 14 700 - 15 150 + 14 800 - 20 R = 300 H + H + H 1 3 2 Average H = 175 + 13 900 - 25 1 200 + 12 1000 - 30 250 + 11 1200 - 35 C = + 10 1 300 + 10 1400 - 45 C = + 5 350 + 5 1600 - 50 2 400 1800 - 60 3.5’+3.4’+3.3’ 3 Average H = R = 350 450 - 2 2000 - 65 2 = 3.4’ Interpolation Formula C = (C - C ) 2 1 (R - R ) x (R - R ) + C A = W x H = 20.2’ x 3.4’ = 69 sq.ft. q = V x A C = ((+ 5) - (+ 10)) (350 - 300) x (310 - 300) + (+ 10) q = 319 fpm x 69 sq.ft. q = 22,011 cfm C = + 9 fpm Air Velocity = 310 fpm + (+ 9 fpm) = 319 fpm