APPENDIX C

The lower limit of detection of microspheres on the filters can be calculated by using the following equation:

,

where

p = probability,

x = number of microspheres,

T = number of fields of view counted, and

N = total number of fields of view on the filter.

Example:

The limit of detection at the 95% confidence (p = 0.05) for counting 20 fields per filter, with 7100 fields of view per filter the limit of detection is

.