In nogas mode, our standards with Pb don't pick up the correct concentration at one and five ppb (about half). Arsenic, cadmium, and Mercury yield the correct concentrations. Any suggestions on how to get lead on board with our standards?
Sometimes, residual contaminations of Pb can give lower precision for traces.
Can you please check your Background Equivalent Concentration (BEC)?
If your BEC is higher than 1-5 ppb, then it can be the cause.
To get good data, you will then have to chase the source of Pb contamination until you get a BEC lower than 1ppb.
Main sources may be :
Retrieving data ...