LaMotte CARBON MONOXIDE IN AIR TEST KIT - Manual (Page 2)

IN TRO DUC TION
Carbon monoxide is a poisonous inhalant, and great caution must be
exercised when working with this odorless and colorless gas.
At a
concentration of approximately 1000 ppm carbon monoxide kills quickly.
A 50 ppm concentration is generally considered the upper limit of safety
in industry for healthy persons within certain age ranges when exposure
may continue for an eight hour period. Concentrations of carbon
monoxide may reach hazardous levels in garages, tunnels, behind
automobiles, or in the open atmosphere under certain conditions. All
work with the carbon monoxide testing unit should be supervised by
qualified personnel.
The carbon monoxide testing unit relies upon the use of a single reagent
for a unique, quantitative measurement of carbon monoxide
concentrations. This method requires the use of an axial reader for the
measurement of faint color reactions.
Since the re ac tion of the *Car bon Mon ox ide Ab sorb ing So lu tion (7799)
with car bon mon ox ide pro duces a yel low color, and the re agent is slightly
yel low it self, it is nec es sary to per form a re agent blank. The re agent blank
is then sub tracted from the test re sults. The con cen tra tion of the re agent
blank must be de ter mined us ing the in for ma tion for the same sampling
period as the actual test procedure. For example, if the reagent blank
matched the index of 1, and a 30 minute sampling period was chosen for
the test, it would correspond to 20 ppm (from the 30 minute sampling
time line on the chart). If the resulting color of the reaction, after a 30
minute reaction time, was determined to match an index of 5, this would
correspond to a concentration of 100 ppm. The test result would be 100
ppm minus 20 ppm, or 80 ppm carbon monoxide.