Some notes for sampling:
- One flask per sample is sufficient, minimum volume is 40 mL except for Ultra Pure Water.
- Do not treat samples! No filtration, no additives, no freezing.
- Use powder-free gloves for sampling, if possible.
- On the day of sampling please do not use perfumes, hair conditioners, creams, etc.
- During sampling try not to speak, sneeze or cough.
- If possible, label the flasks with self-adhesive labels before sampling. If you do not know the precise sampling sites, mark flasks in consecutive order
and note sampling sites separately. WHY?: Felt pens release organic solvents!
- Before you sample, think about where to put the closure that it will not be contaminated! At site, rinse flasks 2x with sample, then sample and close.
Leave some air space in the flask. If your sample contains reduced ground waters: Precipitation of iron can be prevented by filling flasks ”bottom-up” with a tube, prevent air space.
- For “hot” waste waters (before treatment) and in case of slow shipment of samples at warm seasons we recommend to pasteurize closed flasks before shipment.
Pasteurize samples in a water bath for 15-30 min at 65-80 °C. At site you may use a tea-kettle:
Insert the flask, fill the kettle with tap and let water boil, turn heating off and keep flask for 10 min in the boiler. Make sure labels do not come off and are still readable, otherwise label after pasteurisation.
- Sampling volumes
These are the volumes we need at least per sample analysis:Standard Marine Ultrapure Sum. DOC Volume > 40 mL > 40 mL 1000 mL > 40 mL
Special advises for sample types
- We do not charge extra for sample pre-treatment, like neutralisation or membrane extraction.
- Minimum sample volume is 40 mL.
- With slight adaptations of chromatographic conditions, LC-OCD-OND can also be used to analyse NOM in marine waters.
- Minimum sample volume is 40 mL.
- Please mark ”marine samples” on flask or accompanying letter.
- Since 2004 we are capable to characterise organics in waters with TOC-values in the sub-1-ppb concentration range after preconcentration.
This includes the identification and quantification of compounds including NOM, urea and resin leaching compounds in the ppt range.
- The price for one LC-OCD-OND analysis of UPW is higher, as this includes pre-concentration, the analysis, and a full individual report
with interpretation on the basis of the analytical data and (optional) additional information given by customer.
- Minimum sample volume is 1000 mL.
- DOC-Labor also offers summaric DOC-analyses, particularly for waters below 200 ppb.
- The minimum order volume 2x analyses.
- Minimum sample volume is 40 mL.
- Find further information within our downloadable instructions: Sampling and Shipping
(link will open in a new window)