AVERAGE HEIGHT AVERAGE WIDTH 19 5 7 2

AVERAGE HEIGHT = AVERAGE WIDTH = 19. 5’ 7. 2’ 7. 3’ 7. 5’ 19. 8’ AREA = AVERAGE TIME = 15 SECONDS 14 SECONDS 7. 3 19. 6 18 SECONDS 16 SECONDS 20 SECONDS 83 6 143 14 SEC. AVERAGE VELOCITY = 10’/14 =. 7 X 60 = 42 X 0. 9 = 38 FPM 10’/14 equals fps, we need fpm so multiply fps x 60 seconds will give your fpm. The 0. 9 is multiplied by fpm per MSHA bulletin restriction factor. q=Vx. A q = 38 fpm x 143 sq. ft. = 5434 cfm

1. If you take three (3) height measurements in an entry of 7. 2’, 7. 5’ and 7. 3’ then what is that average? ______ 2. If you multiply your height average by the average width of 19. 8’ + 19. 5’ = 39. 3’/2 = 19. 6’ then what is your area of that entry? _______ 3. If you take two timed smoke cloud readings in each third of an entry of 15, 14, 18, 16, 20, 0 then what is your average time of those readings? _______ 4. If you have your distance of your smoke cloud which is 10 feet and your average time then what is your FPM? Remember your formula is distance (10’) divided by your average time _____ equals ___fps. (You need to multiply by 60 to convert feet per second to feet per minute) Then multiply that number by 60 seconds equals ____fpm. Then multiply that by 0. 9 (per MSHA correction for flow) to get final FPM ______. 5. Now what is your CFM, if you have your FPM _____ and you multiply that by your area ______. CFM equals _______.