Membrane cleaning, WPS photoshoot 08_10_2028

Water Filtration and RO Membrane Autopsies

An RO membrane autopsy is beneficial when there is a decline in water filtration performance but the cause is unknown. Nalco Water uses a destructive autopsy procedure to analyze the foulant in the membrane itself. We can determine when the autopsy should be done, perform it for you and interpret the results.

The membrane inspection identifies the type of fouling, scaling and damage to the membrane, and we can recommend steps to resolve the issues. Nalco Water has some of the largest and best-equipped laboratories in the world that specialize in this type of work.

RO Membrane Autopsy Process

Nalco Water has water filtration specialists who are able to:

  • Recommend when to use an autopsy procedure. Generally, we recommend the autopsy only when a detectable biofilm or fouling layer is present.
  • Perform the autopsy. We look at current performance, dissect the membrane and check for damage caused by mechanical issues, fouling or chlorine.
  • Provide clear results. In addition to the autopsy results, we provide recommendations to help you determine the best strategies for mitigating the membrane fouling problem.


The autopsy can include:

  • Specialist selects the representative element(s)
  • Dissection of a fouled membrane element to reveal the membrane leaves and plastic spacer material
  • Chemical, microbiological and microscopic examination
  • Crossflow test cells to characterize membrane performance
  • Identification of the key foulants
  • Documentation through photographs
  • Remedies and recommendations