Iron related bacteria include both iron oxidizing and iron reducing bacteria. These bacteria function under different reduction-oxidation (redox) conditions and utilize a variety of substrates for growth.  This consortium is complex and includes stalked and sheathed bacteria as well as heterotrophic and slime forming bacteria. Examples of this group include: Gallionella, Crenothrix, Sphaerotilus, Siderocapsa, Thiobacillus and Pseudomonas.  

The iron utilizing bacteria can be problematic in that they can cause corrosion of iron and steel.  This process can cause pitting of the metal surface, resulting in pin-hole leaks. These bacteria can also accumulate iron to the point where the growth becomes a hard encrustation or tubercle. Over time these deposits can reduce water flow and affect system performance.  

 Types of water that can be tested include: potable water plumbing systems, cooling towers, heat exchangers, water heaters, and water based fire protection sprinkler systems.

Test Method: 

IRB-BART™ Biological Activity Reaction Test for Iron Related Bacteria. Manufacturer: Droycon Bioconcepts Inc. Saskatchewan, Canada

Turn Around Time

10–12 days

Test Code


Sampling Instructions

Note: These bacteria and their affects are often associated with water in low flow areas. Sample collection will vary by source.  The test is semi-quantitative; therefore, once collected, the sample should be shipped to lab within 24 hours with a cold pack. Generally, collect samples as follows:

  1. Complete SPL Chain of Custody form provided. 
  2. Use waterproof pen to label bottle with sample location, description, and date. 
  3. Samples for more than one MIC test maybe collected in single 250 ml collection bottle as long as there is  ≥30 ml for each type of test requested.
  • Cooling Tower and Non-potable Water
    1. Submerge open bottle just under the surface of water to obtain ≥30 ml of sample. Avoid sediment. 
    2. Close bottle and invert to mix the sodium thiosulfate neutralizer.
  • Potable Water
    1. Turn on water (hot or cold) and immediately fill bottle to ≥30ml.
    2. Close bottle and then invert to mix the sodium thiosulfate neutralizer.

Sample Transport 

  1. Deliver or ship samples the same day they are collected. The time from sample collection to analysis should not exceed 24 hours.
  2. Place bottles in box with insulated liner..
  3. Place completed Chain of Custody in plastic document holder and pack in box.
  4. Ship overnight Monday–Thursday only to: Special Pathogens Laboratory, 1401 Forbes Avenue, Suite 401, Pittsburgh, PA 15219

Questions? Call SPL at 412-281-5335