As part of a membrane pilot evaluation conducted by CH2M HILL for the City ofWestminster, Colorado, integrity testing was performed for Memcor CMF-S, Pall Microza, and ZenonZeeWeed. The purpose of integrity testing was to assess the capability of conventionalmethods in detecting a breach in a membrane fiber. In addition, the experiments allowedfor the comparison of a relatively new monitoring method (laser turbidimetry) to theconventional integrity monitoring methods.The instrumentation used to monitor the condition of permeate water produced by thepilots included IBR online particle counters, conventional Hach 1720C turbidimeters, as wellas three experimental turbidimeters which were being field tested. The three experimentalturbidimeters (designated as A, B, and C) were approximately 100X, 800X, and 7000X moresensitive than the conventional Hach 1720C. Includes tables, figures.