DI Water Compatibility Chart
We design and sell a complete line of DI and RO/DI hybrid water processors. So we naturally get a lot of request for information about DI material compatibility. The table below lists the most common interactions. Talk to your local Clean Water Crusader if you require more information.
Common Industrial Materials and their compatibility with deionized water
|304 stainless steel||A1-Excellent|
|316 stainless steel||A2-Excellent|
|Buna N (Nitrile)||A1-Excellent|
|Carbon Steel||D-Severe Effect|
|Cast iron/Galvanized Iron/Ductile/Black Iron Pipe||D-Severe Effect|
|ChemRaz (FFKM)||D-Severe Effect|
|Polyetherether Ketone (PEEK)||N/A|
Ratings – Chemical Effect
A = Excellent
B = Good
Minor Effect, slight corrosion or discoloration
C = Fair
Moderate Effect, not recommended for continuous use. Softening, loss of strength, swelling may occur
D = Severe Effect, not recommended for ANY use.
N/A = Information Not Available.
Explanation of Superscript
1. Satisfactory to 72°F (22° C)
2. Satisfactory to 120°F (48° C)
Some of the questions that I’ve received about this page:
Q: An Auditor questioned our use of a rubber hose and Tygon tubing for transfer of DI water in our BOD testing. Was wondering if these are acceptable?
A: Certain rubbers can add to the BOD and/or COD of the water, especially at elevated temperatures.
More importantly, when BOD is critical and the process requires in-situ disinfection, rubber interacts negatively with most disinfectants and creates a home for biofilm; so I generally advise against rubber tubing where BOD is important.
Tygon generally doesn’t impact BOD (unless bacterially contaminated) and works better with a broader range of disinfectants.
When selecting tubing, also make sure that the tubing is certified for the application at the temperature.
Q: Do you have any data with RO water compatibility with stainless steels at 180 F?
A: At higher temperatures, the effects of water chemistry and dissolved gases are significantly more pronounced.
As long as your purified water chloride level is <5ppm and your dissolved CO2 and O2 are low, one would not expect to see any corrosion or premature failure with stainless steel.