ANALYTICAL CHEMISTRY again double. Using Figure 6 for correcting the visibilities as recorded to the average relative humidity of 55%, the curve then appeared as the dotted one in Figure 5. The corrected visibility curve is now a very nice inverse function of the K , curve. 100-
’
90-
tion for evaluating air pollution levels. The K , value should be thought of as proportional to the total mass of particulate material, normally dark colored, in the air per unit of volume. The K,,, values may be used directly for comparative purposeg, or they may be converted to represent any particular related constituent component, such as the carbon or lead, for checking programs for control of air pollution. Visibility readings, as such, are not satisfactory as a measure of particulate mass concentration.
80-
5 W
V
. ... , ._ .... . _ .. . ... 70’.’:.\....
