DEREK POPP is the quality control coordinator at the Wisconsin Occupational Health Laboratory in Madison, Wisconsin. Popp serves on the AIHA Proficiency Analytical Testing Programs LLC Board and is past chair of AIHA’s Sampling and Laboratory Analysis Committee.
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Choosing an Industrial Hygiene Laboratory
When you need industrial hygiene sample analysis, you want a laboratory with the relevant specialization. A lot of very good environmental laboratories say they can analyze IH samples, but their expertise is quite different, so focusing on labs accredited for IH is a good start. To further narrow your choices, you need to determine which labs perform the specific analysis you’re interested in. This information is available from accreditation bodies such as AIHA Laboratory Accreditation Programs LLC, which identifies the fields of testing and test methods for which each IH lab is accredited. Looking at the labs’ websites also provides a sense of their services. Ultimately, though, you’ll need to contact the labs directly.
MAKING CONTACT Whether you call or email, you’ll end up talking to a customer service representative or another staff member. During either this initial conversation or follow-up conversations, try to develop a fuller impression about how the lab operates.
For example, as a lab customer, can you contact technical staff directly? If not, are the customer service specialists knowledgeable enough to answer questions, or will they take a message and have one of the analysts get back to you? You need to be sure that you can get answers quickly.
Ask for the lab’s quality assurance plan, copies of recent proficiency testing results, pricing for specific analyses, billing practices, and turnaround time. Detection and reporting limits are important to a lot of IHs, but you need to know what to ask. Good questions include “How were the detection or reporting limits determined?” and “What is the uncertainty around the value?” The determination and verification of detection and reporting limits should use the analyte of interest on the actual collection media and should follow a recognized procedure such as the EPA methodology in 40 Code of Federal Regulations 136 Appendix B.
If the labs you’re considering have different reporting limits, they may have different levels of uncertainty as well. A lab might accept more error at low levels, which allows for a lower reporting limit. It’s also important to remember that the detection limit is less than the quantification limit, and the quantification limit is less than the reporting limit. (The Synergist article “Detected or Not?” includes a thorough discussion of these terms.)
Detection and reporting limits are important to a lot of IHs, but you need to know what to ask.
Ask what the lab’s normal turnaround time is. Can you pay extra for faster service? If you need lab reports or other deliverables electronically, make sure the lab can meet these requests.
Ask for a written procedure for method validation and method development. Some labs have different levels of validation. It is important that the lab has analyzed laboratory-prepared samples on collection media before analyzing customer samples. If you will be collecting samples of analytes that don’t have methods, find out how open the lab is to method development. Extending a method to cover new, similar analytes is much easier than developing a method with little information. Even with an analytical procedure, coming up with collection media and verifying that it works can take a lot of time.
If you are looking at local labs, consider asking to take a tour. Tours give you a sense of the lab’s capabilities and a chance to talk to key individuals who will be analyzing your samples.
Price will be a factor. Ask to see a price list and note the costs for media (if supplied by the lab) and electronic reporting. If you will need methods developed, get an idea of those costs before making your decision.
FINAL DECISION There are many factors to consider when selecting a lab. Once you’ve narrowed your choices to accredited providers with relevant expertise, the decision comes down to how comfortable you are with the people you’ve met and the value the lab can provide.