Be prepared – mobile outdoor measurement
Summertime is high season of spot measurements of standard parameters. Everywhere people are measuring in surface and ground water. Basically the entire equipment has to be in excellent condition avoiding additional efforts or even the abrupt termination of a measurement campaign.
A checklist helps covering all requirements:
- Are my meters ok? Are the connectors clean, the rechargeable batteries fully loaded, do I have replacement batteries? When travelling for a couple of days it might be useful having more than one meter available.
- Have the pH electrodes been calibrated properly? Are slope and asymmetry within the appropriate range? Buffers, storing solution, distilled water should be part of the equipment, as well as clean plastic beakers. Carrying a replacement electrode is recommended, breaking the glass parts of an electrode in streaming water is not uncommon.
- Conductivity cells are very robust; they only require a visual inspection of electrodes and cable. According to the standards they have to be tested within a half year interval in standard solutions, usually no problems occur.
- For oxygen sensors two cases have to be considered: After a long storage or use particularly electrochemical sensors should calibrated to evaluate the relative slope. If there is any doubt the old membrane cap should be replaced. Clean the electrode according to the manual, fill a new cap and screw it on the sensor. Make sure to leave it until the polarization time is over.
Optical sensors can be tested with the check function of the meter. It might help to check the membrane cap visually on damages (visible green flashing of the LED or spalling of the membrane). It is recommended to check the cables for any damage as well.
- Last not least: Is everything prepared for documentation? Clip boards, paper, pencils or a laptop with evaluation software and connection cables?
Done? Good luck for a successful campaign!