Technical hoses come into contact with a wide range of media – from water and oils to aggressive chemicals. To ensure that a hose is suitable for the intended application, Hose-Center Garditech® provides a comprehensive Chemical resistance list. But what exactly do the symbols in this chart mean – and how should you interpret the table correctly?
We’ll give you an overview below.
What does chemical resistance mean?
Chemical resistance describes a material’s ability to withstand a specific medium (e.g. acid, alkali, oil) without being damaged or losing its properties. Depending on concentration, temperature, contact time, and the medium itself, a hose may react differently.
Overview of symbols
Our resistance charts use a simple yet proven marking system:
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“+” = resistant
→ The hose can be used continuously with the medium without any impairment. -
“0” = conditionally resistant
→ Suitable only for short-term contact or under certain conditions (e.g. limited temperature range). -
“–” = not resistant
→ The hose is not suitable for this substance. Brittleness, leakage, or failure may occur.
You may also find combinations such as “+0” or “–0”, indicating restricted conditions (e.g. limited temperature range or concentration).
Practical examples: Sulfuric acid & diesel
A quick comparison shows how different the ratings can be:
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Sulfuric acid (10%) → “+”: PVC hoses can be used safely at this concentration.
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Sulfuric acid (96%) → “–”: Highly corrosive – not suitable for PVC.
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Diesel oil → “0”: Conditionally resistant, suitable for short-term use at room temperature.
These differences clearly show that concentration and application context are crucial.
What should you keep in mind when interpreting the list?
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Temperature: The values usually apply to room temperature (approx. 20 °C). At higher temperatures, resistance may decrease.
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Concentration: A diluted medium may be harmless, while a concentrated one can damage the material.
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Duration of exposure: Short-term contact is often less critical than continuous use.
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Pressure: High operating pressure combined with chemical exposure can further reduce hose life.
Conclusion: A guide – but not a substitute for expert advice
Our resistance charts provide a solid basis for selecting the right hose. However, for critical media or special applications, we always recommend an individual consultation with our technical sales team.
