# Legionnaire's disease and airconditioner technology

**URL:** <https://boards.straightdope.com/t/legionnaires-disease-and-airconditioner-technology/18251>\
**Category:** Factual Questions\
**Created:** [May 1, 2000, 1:56pm UTC](https://boards.straightdope.com/t/legionnaires-disease-and-airconditioner-technology/18251 "2000-05-01T13:56:08Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![hawthorne](https://avatars.discourse-cdn.com/v4/letter/h/c89c15/32.png) [@hawthorne](https://boards.straightdope.com/u/hawthorne)\
**Post date:** [May 1, 2000, 1:56pm UTC](https://boards.straightdope.com/t/legionnaires-disease-and-airconditioner-technology/18251/1 "2000-05-01T13:56:08Z")

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In my town, we are in the midst of a bit of an outbreak of Legionaire’s disease. As usual, the source is an airconditioning cooling-tower.

What strikes me as odd is that the building - the Melbourne Aquarium - is brand new: it has only been open for a couple of months.

Given that cooling-towers provide ideal conditions for the growth of legionnella bacteria, why is some kind of sterilization not built into the cooling-tower process of new buildings?

picmr

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**Author:** ![casdave](https://avatars.discourse-cdn.com/v4/letter/c/c6cbf5/32.png) [@casdave](https://boards.straightdope.com/u/casdave)\
**Post date:** [May 1, 2000, 4:10pm UTC](https://boards.straightdope.com/t/legionnaires-disease-and-airconditioner-technology/18251/2 "2000-05-01T16:10:41Z")

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There usually is a sterilising system.

Systems I have seen use dosing pumps that inject the small amounts of biocide accurately or else ,in a big system I worked on once, chemical pellets like very large aspirins were fired in using a compressed air injection system.

The problem is getting the dosing right, the chemicals are toxic and expensive.Samples of the cooling water have to be taken and the concentrations of chemicals checked, from time to time samples have to be sent to labs for bio-analysis.

When these things happen it nearly always turns out to be a failure in the routine maintenance schedule and its operation.The fines and compensation claims for failure to do these thing correctly can be huge, my bet is that there will be a few heads rolling over this.

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**Author:** ![Alphagene](https://avatars.discourse-cdn.com/v4/letter/a/8e7dd6/32.png) [@Alphagene](https://boards.straightdope.com/u/Alphagene)\
**Post date:** [May 1, 2000, 10:14pm UTC](https://boards.straightdope.com/t/legionnaires-disease-and-airconditioner-technology/18251/3 "2000-05-01T22:14:36Z")

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[What is being done to prevent legionellosis?](http://www.cdc.gov/ncidod/dbmd/diseaseinfo/legionellosis_g.htm)

> [@](#):
>
> Improved design and maintenance of cooling towers and plumbing systems to limit the growth and spread of Legionella organisms are the foundations of legionellosis prevention.