Table of Contents
Advertisement
average replacement interval is one to two weeks. Probes in
constant or heavy use may require more frequent membrane
changes.
Interferences
Hydrogen sulfide, sulfur dioxide, halogens, carbon monoxide,
chlorine, nitric oxide, and nitrous oxide can cause the probe to
give erroneous readings. If you suspect erroneous readings, it
may be necessary to determine if these are the cause.
Acids
Avoid any environment that contains substances such as
concentrated acids, caustics, and strong solvents that may
attack the probe. Probe materials that may be damaged by
these substances include FEP Teflon, EPR rubber, ABS
plastic, and stainless steel.
Erroneous Readings
Erroneous readings may occur if the membrane is coated with
oxygen consuming bacteria or oxygen evolving algae. Heavy
residue may coat the membrane causing incorrect readings.
Frequent membrane changes will eliminate this problem.
Storage
When the probe is not in use, store the probe in a BOD bottle
containing at least 1 inch of water. For long term storage,
remove the membrane cap, rinse the probe tip with deionized
water, and install a dry membrane cap (without electrolyte
solution).
8
Advertisement
Table of Contents
