There is a generally recognized need for methods that permit rapid estimation of the bacteriological quality of water. Applications of rapid methods may range from the analysis of wastewater to potable water quality assessment. In the latter case, during emergencies involving water treatment plant failure, line breaks in a distribution network, or other disruptions to water supply caused by disasters, there is urgent need for the rapid assessment of the sanitary quality of water.
Ideally, rapid procedures are reliable and have sensitivity levels equal to those of the standard tests routinely used. However, the sensitivity of a rapid test may be compromised because the bacterial limit sought may be below the minimum bacterial concentration essential to rapid detection. Rapid tests fall into two categories—those involving modified conventional procedures and those requiring special instrumentation and materials.