Legionella Testing / Biosafety Training
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Legionella Testing

Accurate Legionella Testing Laboratory

How We Operate:

Since 1981 we have quantitatively tested thousands of samples for legionella from water-containing mechanical equipment and plumbing lines. Contact us to receive our test agreement, chain of custody form, and sampling instructions for legionella bacteria testing. We ship sterile, 120 ml sample bottles and labels by USPS Priority Mail. Turnaround time is usually three business days. We email you your test report(s), interpretation of test results, and industry-suggested legionella decontamination methods if needed.  
 

Why Test for Legionella?

Legionella testing validates whether your legionella control procedures are working. The authors of the May 2015 AIHA guideline, “Recognition, Evaluation, and Control of Legionella in Building Water Systems”, state that the ASHRAE Standard 188 “is all but silent on how to validate the effectiveness of control measures used to prevent legionella amplification”… “Which is akin to measuring temperature and ventilation rates at a refinery to gauge the effectiveness of controlling benzene exposure rather than sampling for benzene itself and determining the actual exposure level.”


Excellent Information Source: LEGIONELLA 2003: An Update and Statement by the Association of Water Technologies (AWT)
 

GTS Legionella Test Method:

We use the gold standard quantitative direct fluorescent monoclonal antibody (DFA) test for 14 serogroups of Legionella pneumophila and 15 other Legionella species associated with human disease. We use a modification of the original DFA method published by the CDC in 1978 by William B. Cherry. Our test method was published in 1985. Water Research Vol. 19, No. 7, pp.839-848, 1985 - except for a change to more specific monoclonal antibody DFA reagents.
 

Why We Don't Use the Culture Method:

Legionella on BCYE agar media are often overgrown or inhibited by competing microbial flora that mask the presence of legionella colonies, particularly with water samples taken from warm water-containing mechanical equipment exposed to the environment such as fountains, cooling towers, and saunas. Culture on BCYE agar with or without supplements, antimicrobial agents, water sample heat or acid treatment lacks the sensitivity of our quantitative DFA test. New legionella laboratories using the voluntary Wisconsin State Laboratory of Hygiene Elite culture method for legionella bacteria testing may not report accurate test results. Investigation at a Veterans Affairs Medical Center of Spurious Legionella Environmental Testing Results and High Laboratory-to-Laboratory Variability Among Four CDC Elite Commercial Laboratories.

Legionnaires' Disease Current Information:

Remedial Action:

There are no government regulations specifying permissible numbers of legionella in water systems. When numbers of legionella in a water sample are significant, we suggest decontamination of water systems using industry-standard procedures such as the State of Wisconsin Department of Health Guidelines as modified by the Cooling Technology Institute. ASHRAE and EPA have also published decontamination procedures. 

Legionella DFA

Legionella DFA

CDC Symposium 1978

CDC Symposium 1978

ASM Legionella 1984

ASM Legionella 1984

CDC Legionnaires 1978

CDC Legionnaires 1978

CDC Legionnaires 1979

CDC Legionnaires 1979

Legionella Sources-CDC

Legionella Sources-CDC

Legionella DFA

Legionella DFA