What does MPN stand for in the context of fecal coliform measurement?

In the context of fecal coliform measurement, MPN stands for Most Probable Number. This statistical method is used to estimate the concentration of viable microorganisms in a sample, specifically fecal coliform bacteria, which are indicators of water contamination. The MPN technique involves a series of dilutions and inoculations followed by observation for microbial growth, and it provides a numerical estimate of the bacteria present based on observed growth patterns.

This method is particularly valuable in water quality testing because it allows for the determination of coliform levels in a sample without requiring specific bacterial isolation. The value derived from MPN reflects the statistical likelihood of finding a certain number of coliforms, making it a standard practice in assessing the microbial safety of drinking water and recreation waters.

Other choices, while plausible-sounding, do not reflect established terminology in microbiological analysis. Understanding MPN is crucial for wastewater operators, as it directly impacts public health assessments related to contaminated water sources.