ELITE enrolment and accreditation: how to check a legionella laboratory

Somebody has to run the culture, and choosing who is the one decision in this field that a building operator makes alone, usually once, often under time pressure, and almost always without being able to judge the answer.

The good news is that the judgment reduces to two questions. The bad news is that they are routinely presented as one question, and the merge is where buyers get hurt.

The two things, kept apart

ELITE enrolment is proficiency. The Environmental Legionella Isolation Techniques Evaluation program sends enrolled laboratories blind panels twice a year and scores whether they recover what the panel contains. It measures one thing, and measures it well: whether that bench can find legionella when legionella is there. It is the only national signal of its kind in the United States.

Accreditationis a different assessment entirely. It examines the laboratory’s quality system, held under ISO/IEC 17025 or a state program such as New York’s ELAP, and it covers the things that decide whether a result is defensible: method validation, calibration, competence records, corrective action, and the scope of what the laboratory is accredited to do.

A laboratory can hold either without the other. A supplier who tells you that ELITE enrolment makes a laboratory accredited is either confused or hoping you are, and that sentence is worth testing them on, because it is a good predictor of the rest of the conversation.

The scope line matters more than the certificate

An accreditation certificate is issued for a defined scope: named methods, for named matrices. A laboratory accredited for drinking water chemistry is genuinely accredited, and that tells you nothing about legionella by culture from a cooling tower.

So the request is not “are you accredited”. It is: send me your accreditation certificate and the scope page, and tell me whether you are currently enrolled in ELITE. A laboratory that holds both answers in one email without being chased. One that sends a logo, a badge image, or a sentence in a brochure has told you something too.

Why absence from the public roster proves nothing

Appearing on the public ELITE list is optional. CDC has described the program as having over two hundred participants; far fewer have consented to appear publicly. A laboratory missing from the published roster may simply have declined to be listed, so the roster is a starting point and never a verdict. It is published here, by state, on the laboratories page.

Questions that sort the field

What method, and what does the report contain? The report should say what was found, where, by which method, and under what conditions the sample was taken. A number with no conditions attached cannot be compared to anything later, which defeats the purpose of sampling more than once.

What holding time do you require, and how is it met? The constraint that actually binds is the time between collection and the start of culture, not the distance. This is also why a laboratory two states away can be a better answer than a nearer one.

What bottle, and what neutraliser? Matched to the disinfectant in the system. A laboratory that does not ask what is dosed in your system before sending bottles is not paying attention.

What else do you sell? The structural question. A company that also treats water, cleans towers or sells chemicals has a stake in what the result shows, and a sample taken after its own remediation is marking its own work. That is not an accusation, it is a structure, and a buyer is entitled to know it before rather than after.

Where this sits in the program

Choosing the laboratory is a validation-stage decision, and validation is element six. If you are choosing a laboratory before you have a written program, the order has gone wrong, and the result will arrive with nothing to compare it against. What the program has to contain is in what ASHRAE 188 asks of a building, and the builder assembles a draft of it in seven steps.