MIC Remediation and Why You Should Have Your Fire System Checked

The fire safety system in your commercial or industrial building is a critical safety feature intended to prevent injuries, protect property, and save lives. Regular inspections and maintenance of this system ensure that it functions properly and will be ready if needed. Standard inspections, however, may not be enough to keep your fire sprinkler system in working order. MIC remediation and careful checks for related damage should be included as a regular part of fire system maintenance.

What is MIC?

MIC stands for microbially influenced corrosion. It is a type of damage to sprinkler pipes and metal components caused by specific types of microorganisms. The microbes and bacteria that cause MIC are present in almost all municipal water supplies in the United States and elsewhere. MIC-causing microbes and bacteria literally eat away metal and cause severe damage to plumbing pipes. Within the pipes of your sprinkler system, these microorganisms attach to the walls and establish colonies, known as nodules. These nodules consume the metal of the sprinkler pipes, creating small holes that can cause water leaks or loss of water pressure. MIC has been found in pipes made of galvanized steel, copper, stainless steel, and ductile iron. If your fire sprinkler system has been affected by MIC, it could fail or be ineffective whenever it’s activated to suppress a fire.

MIC Remediation with Biocides

MIC remediation should be included as part of the regular maintenance and inspection of your fire safety system. This process is intended to locate and remove any existing nodules of MIC-causing microorganisms and create conditions within the pipes that make it difficult for these microbes and bacteria to grow and thrive. Biocides are commonly used for MIC remediation in fire safety systems. These substances are intended to kill the microorganisms that attack your sprinkler pipes and prevent reestablishment of MIC-causing nodules. This has been effective, but there are several drawbacks to using biocides for this purpose:

• Biocides are poisons that can be harmful to human health. If they are used in a sprinkler system that could discharge in a public area, such as a shopping center, they could present a health risk to anyone exposed to them.
• The use of biocides could lead to insurance liabilities for companies or lawsuits from persons exposed to them.
• Biocides can be harmful to the environment, increasing the chance of problems with local wildlife populations and any environmental regulation compliance.
• MIC-causing microorganisms can become immune to biocides over time. This means that different biocides must be used in the same sprinkler system. As microorganisms adapt, they become immune to more and more types of biocides.

MIC Remediation with Coatings

MIC remediation with pipe coatings can be a safer and more effective solution to MIC problems. The coatings are applied inside the sprinkler system pipes to prevent microorganisms from forming nodules and starting colonies. There are several types of coatings that have been used in fire safety systems:

• Permanent biostatic coatings: These coatings contain molecules that prevent MIC-causing microorganisms from attaching to pipe walls and starting colonies. When installing fire protection systems, care must be taken to ensure that all surfaces are covered with these coatings. Any new welds, connections, valves, or sprinkler heads that are uncoated will be susceptible to MIC.
• Dynamic biostatic coatings: Dynamic coatings also prevent MIC-causing microorganisms from starting colonies. However, these coatings are somewhat water soluble, which means some of the material will enter the water within the pipe and coat untreated areas inside the system.
• Conventional coatings: Paint and other conventional coatings create a physical barrier against microorganisms, but they can crack over time and expose pipe surfaces.

Our goal is to help educate our customers about Plumbing, HVACR, Fire Protection, and Alarm Systems in Mechanical, Commercial, and Residential settings. For more information on MIC remediation and preventing MIC from damaging your fire safety system, and to view projects we’ve worked on, visit our website!