Rating
| Concentration | 20 °C | 50 °C | Remark |
|---|---|---|---|
| 12,5 % Cl | B | B | pitting risk |
| 15 % | B | B | pitting risk |
| dilute | B | B | pitting risk |
| saturated | B | B | pitting risk |
Material comparison at 20 °C
Resistance overview
SS 316 maintains a consistent rating of B across all 4 tested concentrations (12,5 % Cl, 15 %, dilute, saturated) of Sodium Hypochlorite (Bleach) at 20 °C. The fact that the rating does not change with concentration within the tested range simplifies material selection, though the boundary conditions beyond this range remain untested. The rating remains stable between 20 °C and 50 °C, which means this material can also handle moderately elevated process temperatures without additional risk. Note that the source flags a risk of pitting or stress-corrosion cracking for this combination, which is particularly relevant for pressure-bearing or structurally loaded components.
Application context
Sodium Hypochlorite (Bleach) is commonly encountered in waste treatment and bleaching. SS 316 (Stainless steel 1.4401 (AISI 316)) is a metal typically used for vessels, heat exchangers, fittings and structural components. Because Sodium Hypochlorite (Bleach) is classified as corrosive, the choice of containment material is especially critical to prevent leaks, equipment damage, and safety hazards.
Practical recommendation
SS 316 is suitable for use with Sodium Hypochlorite (Bleach) under normal conditions, but some minor effects on the material are expected over time. Periodic monitoring for swelling, softening, or weight change is recommended, especially for long-service components. For safety-critical or long-life applications, consider PMP, Polystyrene, Polysulfone instead, which are rated A for this chemical.
Did you know?
The chemical resistance of SS 316 depends not only on the chemical concentration but also on exposure time, mechanical stress, and the presence of other chemicals in the mixture.
Materials rated A or B at 20 °C
Based on the row for 15 %, 20 °C.
- Thermoplastics
- HDPE B, PP B, PVC Rigid A, LDPE B, Polycarbonate B, Polystyrene A, Polysulfone A, PMP A, SAN A
- Fluoropolymers
- PTFE A, FEP A, ECTFE/ETFE A
- Elastomers
- Viton (FPM) A
About SS 316
Stainless steel 316 (1.4401) contains molybdenum, which improves resistance to chlorides over 304. Hydrochloric acid and other halide acids still cause pitting.
Rating scale
- A very good resistance
- B good resistance
- C limited resistance
- D not resistant
- – no data
- K no general statement possible
A rating marked * is an estimate in the source, not a test result. An estimate is given as one value without a temperature.
About this data
The ratings come from the chemical resistance list published by Bürkle GmbH, which compiled them from raw-material manufacturers’ data. They describe laboratory tests on the raw material at 20 °C and 50 °C.
A finished part also sees pressure, mechanical stress, welds and mixtures that a laboratory test does not. Treat the rating as a first filter and test under your own conditions before relying on it.