Bacharach Monoxor II Technical Note
621 Hunt Valley Circle
New Kensington, PA 15068
Telephone: 724-334-5000
FAX: 724-334-5001
Printed in U.S.A.
® Registered trademark of Bacharach, Inc.
Technical
Note
TN 95-1
Rev. 0 – December 1995
Accuracy of the Monoxor II
P/N 19-7034 and 19-8004
Bacharach sales and product literature state the accuracy of the Monoxor II to be within
±5 percent of reading in any part of the instrument’s range. This is an accuracy rating, which,
by industry standards, means a limit that measurement reading errors will not exceed. There
are a number of accepted ways to express accuracy. The Monoxor II method is one of the most
stringent.
A recent test on a new Monoxor II chosen at random indicated the accuracy was always within
2 percent of the reading, and accuracy actually improved as the concentration of CO gas
increased. The results of this test are shown below. Tests to determine what happens to the
instrument after repeated readings indicate the instrument will remain this accurate.
The accuracy stated in sales and product literature is conservative. Properly calibrated
instruments will be accurate to an even greater degree than the literature indicates.
0
2
1.
5
0
1.
5
1
1.83
1.5
7
1
1.67
1.8
1.73
1.
5
1.08
1.36
1.47
1.1
3
1.35
1.28
1.05
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
100
200
300
400
500
600
700
800
900
1000 1100 1200 1300 1400 1500 1600 1700 1800 1900
Actual CO in Air, ppm
Read
in
g P
er
cent E
rror
MONOXOR II ACCURACY ANALYSIS
This same data could be reported as 2 ppm or 2% of reading, or 1.15% of full scale.