Question: Can I compare RLU counts to CFU plate counts?

Answer:
The SystemSURE Plus luminometer will detect total ATP present on a surface.  It does not differentiate between the ATP stemming from microbial cells and the ATP from any other residue left on the surface due to inadequate cleaning and sanitation procedures.  Therefore, you cannot directly compare the RLU count from the SystemSURE Plus to any standard plate count results. However there is a very strong correlation between ATP and microbial cells. The presence of ATP on the surface indicates that it has not been adequately cleaned. The primary purpose of cleaning is to remove product residue for product contact surfaces. Effective cleaning simultaneously removes the material capable of supporting microbial survival and growth, as well as many of the microbes themselves. Studies have shown about an 80% correlation.