Minuteman Mirage 27 Propane Burnisher - Manual (Page 18)

Parts and Instruction Manual - Mirage 27” Propane Burnisher Page 11
The direct reading instruments are frequently equipped with audio and/or visual alarms and may be used for area
and/or personal exposure monitoring. Some have microprocessors and memory for storing CO concentration
readings taken during the day.
It is significant to note that some of the devices mentioned for workplace CO monitoring are not capable of
monitoring TWAs, and not all are equipped with alarms. The appropriate monitor must be chosen on an
application-by-application basis. For more information on the availability of workplace CO monitors or their
application, call the National Institute for Occupational Safety and Health at 1-800-35-NIOSH (1-800-356-4674).
Room Size and Time Estimations for Parts Per Million (PPM) CO
The fundamental factors in area CO levels involve the following:

The concentration and volume of CO production

The size of the area

The amount of air exchange if any

The amount of time CO is produced
Multiplying length, width, and height will determine the volume or cubic feet in a room. So an empty building
100ft by 100ft with a 10ft ceiling would be 100,000 cubic ft. in size. Any material that is in the room and takes
space would reduce the cubic feet. Air exchange is defined as the exhausting of internal air to the external
atmosphere. The Graph above depicts the relationships of air exchange to time and CO ppm with cubic feet area
and percent CO emissions remaining constant. 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)
Based on the CO production rates sown 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 period)
The Graph above depicts the relationships of air exchange to time and CO ppm with cubic feet area and percent
CO emissions remaining constant.
1.5% CO 100,000cf Hours of 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 34 118 152 186 220 255
2 change/hr 15 32 49 66 83 100 117 135
8 Hour Time Weighted Average (OSHA Method)