“Finally, we have a ‘fracking’ standard for MEEP analysis!”
Responding to the needs of laboratories testing residential water wells for dissolved natural gases, LGC Standards has answered the call by releasing a new standard that contains 5 parts per million (ppm) of methane, ethane, ethene (ethylene) and propane in water. The Marcellus Shale Coalition Dissolved Methane Method Workgroup learned that labs testing well water for dissolved methane were able to provide “repeatable” data, but not “reproducible” data. Reproducible means that all laboratories will report the same result from the same sample. Laboratories that were part of the Workgroup study reported values between 7.4 ppm and 34.6 ppm from the same sample location. Laboratories have been making their own calibration and QC standards by bubbling gases into cold water, assuming they have made their standard at the correct concentration. Could this be the cause of the reproducibility issue?
The LGC Standards MEEP CRM has a 5 µg/mL nominal concentration, is packaged in a 40 mL VOA vial and arrives with a certificate of analysis containing certified values with uncertainty and traceability data. The product arrives cold by next day air and is guaranteed to have a minimum 45 day shelf life from the date of delivery. We are talking about dissolved gases in water, so after opening, the product expiration is determined by the lab’s own specifications.