There are so many variables to this predicament that it is virtually impossible to foresee a potential MIC "infection". The condition can occur at any time during the life of a piping system (and this doesn't affect only sprinkler systems btw) and due to any number of possible conditions. Also there is not a one-size-fits-all solution or treatment. If a condition is discovered as sample of the growth has to be analyzed, once that's done then a treatment can be recommended. MIC is like a disease, there are many different strains, and each one can require a different treatment.
I was called on a consultation by an owner who had some repair work done and in the process of this work the sprinkler contractor discovered a fairly significant MIC problem. He tried to explain it to the owner who of course had never heard of the problem and thought the contractor was just trying to create more business for himself. Once I explained the reality of it his next mode of response was to look for who to blame and sue so he could recover the cost of repairs and treatment. I explained that it would be virtually impossible to point to any one person or incident that could have caused the problem. The microbes can actually lay dormant for long periods of time, waiting for just that perfect supply of "food" to wake them, and there's no telling how long that could be. Maybe it will be the next flow test of the system you do that will inject just enough oxygen and other materials for them. I would not recommend to any client a preventative system because it will be hard to guarantee 100% effectiveness. Also, the test you do at turn over won't do anything other than verify that the system was MIC free or at least at a limit that can't be measured. Might not be the same next week or next month once things have a chance to begin growing. Unfortunately MIC is almost a more reactionary problem. You can only do so much to prevent it during installation but you have no control of what happens down the road when a repair or remodel is done or there is a contamination issue with the water supply or...... you fill in the blanks. It would be best to not put the burden of MIC testing on the installers as it proves nothing. Scheduled testing and inspections per NFPA 25 and 13 or other applicable standards should discover the problem, then it becomes an issue for the owner to deal with. Catch it early, treat it, investigate potential contamination sources (usually requires an industrial hygienist) and then monitor the systems with closer frequencies to catch any reoccurring growth. Craig L. Prahl, CET Fire Protection Specialist Mechanical Department CH2MHILL Lockwood Greene 1500 International Drive PO Box 491, Spartanburg, SC 29304-0491 Direct - 864.599.4102 Fax - 864.599.8439 [email protected] http://www.ch2m.com -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of George Church Sent: Wednesday, March 25, 2009 10:43 AM To: [email protected] Subject: RE: MIC Design Policy I'd be cautious about assuming every job has MIC and spending (my) money on every job to cure it; perhaps contractually saddle the spkr guy with the testing and specify a couple labs and/or procedure. Make it an allowance if you need to, since most of us aren't going to want to test the water before bid day, heck its hard enough to find out what flow info is available. glc -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of [email protected] Sent: Wednesday, March 25, 2009 10:30 AM To: [email protected] Subject: MIC Design Policy I'll start by saying I assume all of you know more than I do about this subject. My second foray into water quality testing is about all the farther I want to go into this subject. Here's what I have learned: 1. This is an owner requirement but owners don't know they have this responsibility. 2. There may be one handful of labs in the country who are able to do the testing. 3. There is no standard protocol for performing the testing. 4. Ed Schultz made 3 attempts to make positive changes to NFPA 13 (ROP 469, 470, 471) but he got 3 rejections for the '10 edition. However, the committee did add two additional owner options just in case some owner out there stumbles onto this requirement. 5. There's no obligation for the engineer, designer, or contractor to be involved in this subject whatsoever. If not notified by "the owner", then all the rest of us who understand the problem and its consequences can say "the owner" did not inform us. 6. It's pretty clear the committee wants to keep it this way. I'm planning to specify a system treatment approach for every job. Right now I'm leaning toward the Potter approach with the portable chemical injection system. What are the pros and cons of this approach? Bill Brooks William N. Brooks, P.E. Brooks Fire Protection Engineering Inc. 372 Wilett Drive Severna Park, MD 21146 410-544-3620 Phone 410-544-3032 FAX 412-400-6528 Cell _______________________________________________ Sprinklerforum mailing list http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field)
