Dustbane 19315, Parts & Operation Manual

Page: 9 / 48

8 Hour Time Weighted Average (OSHA Method)
1.5%CO 100,000cf Hours Operation 1 2 3 4 5 6 7 8
TWA (OSHA Method) 0 change/hr 34 103 206 343 514 719 959 1232
1/2 change/hr 27 70 124 183 246 311 378 445
1 change/hr 22 51 84 118 152 186 220 255
2 changes/hr 15 32 49 66 83 100 117 135
Based on the CO production rates shown above the TWA would be exceeded in a 100 x 100 x 10 foot (empty) space after
3 hours with 2 air changes per hour. (Assumes no additional CO exposure during 8 hour time period)
1.5% CO Emission in 100,000 cubic feet with 480 cc 14 HP
Engine and complete air/CO mixing
0
50
100
150
200
250
300
350
400
450
500
1 2 3 4 5 6 7 8
Time (hours)
PP
M
(p
ar
ts
pe
r m
ill
io
n)
8
1.5% CO Emission in 500,000 cubic feet with 480 cc 14 HP
Engine and complete air/CO mixing
0
50
100
150
200
250
300
350
400
450
500
1 2 3 4 5 6 7 8
PP
M
(p
ar
ts
p
er
millio
n)
Time (hours)
0 change/hr
1/2 change/hr
1 change/hr
2 changes/hr
0 change/hr
1/2 change/hr
1 change/hr
2 changes/hr
The Graph above depicts the relationships of air exchange to time and CO ppm with cubic feet area and percent CO
emissions remaining constant.
8 Hour Time Weighted Average (OSHA Method)
1.5%CO 500,000cf Hours Operation 1 2 3 4 5 6 7 8
TWA (OSHA Method) 0 change/hr 17 51 103 171 257 360 479 616
1/2 change/hr 14 35 62 92 123 156 189 223
1 change/hr 11 26 42 59 76 93 110 127
2 changes/hr 7 16 24 33 42 50 59 67
Based on the CO production rates shown above the TWA would be exceeded in a 100 x 500 x 10 foot (empty) space after
6 hours with 2 air changes per hour (Assumes no additional CO exposure during 8 hour time period).